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February 2025
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Chemistry 101
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February 24 of 2025
n which of these gas-phase equilibria is the yield of products increased by increasing the total pressure on the reaction mixture? Group of answer choices 2NO(g) + Cl2(g) ⟷ 2NOCl(g) 2H2O2 (g) ⟷ 2H2O(g) + O2(g) 2SO3(g) ⟷ 2SO2(g) + O2(g) PCl5(g) ⟷ PCl3(g) + Cl2(g) CO(g) + H2O(g) ⟷ CO2(g) + H2(g)
(2) Carbon monoxide and chlorine combine in an eq reaction to produce the highly toxic product phosgene (cocle) If the eq constant for this reaction is K_(c)=248, predict, if possible what will happen when the reactants and products are combined The reaction will proceed to the right The…
Question 11Which of the following statements is typically true for a catalyst?1. The concentration of the catalyst will go down as a reaction proceeds./1. The catalyst provides a new pathway in the reaction mechanism.IlI. The catalyst speeds up the reaction. a. I only O b. I and III O c. Il…
The following process may take place in three steps: 2 ClO (g) 2 Cl (g) + O2 (g) S1: 2 ClO (g) ClOOCl (g) S2: ClOOCl (g) ClOO (g) + Cl (g) S3: ClOO (g) Cl (g) + O2 (g) The rate law for this process has been experimentally determined to be Rate = k[ClO]2. Based off this…
If the superanatant liquid is tested with barium chloride, what does this tell you about the reaction? Group of answer choices If a precipitate is formed Cobalt is in excess If a precipitate is formed Carbonate is in excess If a precipitate is formed barium is in excess If a precipitate is…
13. A student measures the pH of a water-based solution to be 8. After the addition of a small amount of a different substance, the pH of the solution increases to 9.a. Did the student add an acid or a base to the solution? Explain your answer.b. Describe what happened to the solution in the…
Question 10 / 1 point When the following pairs of solutions are mixed, which produces the strongest electrolyte solution? Question options: Pb(CH3COO)2 (1 M) + NaI (2 M) Ba(OH)2 (3 M) + CuSO4 (3 M) Zn(NO3)2 (1 M) + AgClO4 (2 M) HCl (2 M) + NaOH (2 M) KCl (1 M) + NH4NO3 (1 M)
In a 0.18mM aqueous solution of trimethylacetic acid C4H9CO2H , what is the percentage of trimethylacetic acid that is dissociated? You can find some data that is useful for solving this problem in the ALEKS Data resource. Round your answer to 2 significant digits.
125I is an isotope used in nuclear medicine and commonly produced by McMaster University in a radioactive concentration of 1014. mCi/mL (Ci, or Curie is a unit of measure of radioactivity). If the half life of 125I is 59.6 days, after production and delivery, requiring 10. days, what would be…
in the context of metallic bonding, what is the "electron sea" model? a model describing the sharing of electron pairs between atoms a model where valence electrons move freely among metal cations, creating a "sea" of electrons a model where electrons are fixed in position with a lattice a…
A bottle of allyl bromide was found to contain a large amount of an impurity. A careful distillation separated the impurity, which has the molecular formula C3H6OC3H6O. The following 13C13C NMR spectrum of the impurity was obtained: Assign the peaks in the 13C13C NMR spectrum to the carbon…
Constitutional isomers are molecules which have the same molecular formula but have different connectivities - or the order they are put together. There are three categories of constitutional isomers: skeletal, positional, and functional isomers. Positional isomers are also called? Group of…
Question 9 (1 point) Saved The law of conservation of matter refers to the fact that Question 9 options: coefficients or subscripts can be changed when balancing a chemical reaction. atoms cannot appear or disappear. in certain cases, matter can be converted to energy. the mass you start with…
Using the mechanism below, what would be the appropriate equilibrium constant expression for the overall reaction? Step 1: 2 Br-(aq) + H2O2(aq) + 2 H+(aq) à Br2(aq) + 2 H2O(l) slow Step 2: Br2(aq) + H2O2(aq) ßà 2 Br-(aq) + 2 H+(aq) + O2(g) fast
The standard Gibbs free energy change for hydrolysis of pure ATP to pure ADP is -31 kJ/mol. The reaction is written [ATP] ↔ [ADP] + [Pi]. What is the Gibbs energy of reaction in an environment at 37 °C in which the ATP, ADP, and Pi concentrations are all 1 mmol/L or 1 μmol/L? (Atkins 4.14)
Suppose your car’s radiator system contains 1.50L of water. How many liters of antifreeze, ethylene glycol (C2H6O2), would you add to the water in your radiator to keep it from freezing if the coldest winter temperature in your area is -25.0oC? (NOTE: The density of ethylene glycol is 1.1135…
Which of the following would be the oxygen pressure entering and leaving this capillary? entering Po2 40 mm Hg, leaving Po2 100 mm Hg entering Po2 40 mm Hg, leaving Po2 45 mm Hg entering Po2 95 mm Hg, leaving Po2 40 mm Hg entering…
galactose is metabolized by a pathway that includes the isomerization of UDP-galactose to UDP-glucose, where UDP = urdylyl diphosphate. curved a are used to illustrate the flow of electrons-pushing arrows for the reaction. uridyl is abbreviated as R. be sure the account for all bond breaking…
Using the tests described in this experiment, how could one distinguish between the following pairs of compounds? Tell what reagent or test you would use and what you would see. a. 1-butanol and 2-butanol b. isobutyl alcohol and rert-butyl alcohol c. 1-propanol and 1-heptanol d. cyclohexanol…
When doing an equilibrium problem based on the following reaction and assuming your initial concentration is 2.0 M, what approximation can you make? HF(aq) ⇄ H+(aq) + F-(aq) K=6.3 × 10-4 2.0 0 0 -x +x +x 2.0-x x x A. x is zero B. x is negligible…
A hypothetical ceramic, Virginium Sulfide (VrS) has a density of 4.306 g/cm3 and cubic unit cell with a cell edge length of 0.512 nm. In addition, we know that: Atomic Wt.: Vr 54.94 g/mol; S 32.06 g/mol Radii: Vr: 0.122 nm; Vr+2: 0.072; S: 0.106 nm; S-2: 0.184 Electronegativity: Vr 1.5; S 2.5…
Question 8Equilibrium is reached in chemical reactions when: a. The forward reaction stops. b. The concentrations of reactants and products become equal. c. The temperature shows a sharp rise.O d. The rates of the forward and reverse reactions become equal.O e. All chemical reactions stop.A…
Two atoms S and O approach each other. The S atom has the following energies of atomic orbitals 1s=-50.1 a.u. ; 2s =-30.5 a.u; 2p=-15.6 a.u; 3s=-10.8 a.u; 3p=-5.2 a.u. The O atom has the following energies of atomic orbitals 1s=-22.1 a.u. ; 2s =-12.5 a.u; 2p=-4.3 a.u. Based on this information,…
Microbes have been found to thrive in which of the following hostile conditions? Select all that apply. Group of answer choices sterilizing radiation 200 atm pressure astroids in deep space above the boiling point of water below the freezing point of water molten lava brine of 30% salt
Why are EDTA specimens obtained before other specimens when collected by dermal puncture? To minimize the effects of platelet clumping. To minimize tissue fluid contamination. To prevent contamination from carryover. EDTA are not collected first. The order of the draw is no different for dermal…
1. Obtain a 50-mL beaker. To determine the mass of the empty beaker, go to a balance, and press the “Tare” or “Zero” button and wait until the digital display reads 0 g. Place the beaker on the balance and record the mass given by the display after it stabilizes. Remember to record all of the…
A 0.580 M Nitrous Acid (HNO2) solution has been mixed with 0.050 M NaCl. What will be the hydronium ion concentration of this solution? The activity coefficients for H3O+ and NO2− are 0.86 and 0.80 respectively. The Ka for Nitrous Acid is 5.10000×10-4.
First ionization energies tend to increase across a period. But in period 2, Be has a higher first ionization energy than B, and N has a higher first ionization energy than O. Explain. [Hint: Look at the valence configurations, and recall that half-filled and fully filled subshells have…
Consider the following reaction: A+B+C→D The rate law for this reaction is as follows: Rate=k[A][C]2[B]1/2 Suppose the rate of the reaction at certain initial concentrations of A, B, and C is 1.11×10−2 M/s .
How much of Clancy's favorite vintage (12% w/w ethanol) must he consume in order to lower the activity of his ADH on methanol to 5% of its normal value if the K_m values of canine ADH for ethanol and methanol are 1 millimolar and 10 millimolar, respectively?
Write out the entire sequence of dissociation reactions starting from H3PO4 to PO43- . Explain equivalence points, where and why species are protonated and deprotonated, and address their buffering capabilities.
What is true about the mass spectrum below? ◻ contains a hydroxyl fragment could be the mass spectrum for 2,2-dimethylheptane could be the mass spectrum for 2,2,3-trimethylpentane could be the mass spectrum for pentane Contains a CH_(2)CH_(3) fragment could be the mass spectrum for cyclohexane
Which of the following sets of quantum numbers represent valid sets? EXPLAIN what is wrong with the ones that are not valid. a. (3, 3, 0, -1/2) b. (2, 1, 0, 1/2) c. (6, 5, -1, 1/2) d. (6, 4, 2, 1) e. (4, 3, 4, -1/2) f. (3, 2, 1, 1/2)
What is the net ionic equation for the reaction of dilute perchloric acid (HClO_(4)) with solid sodium carbonate to produce a gas and colorless solution? A. Na_(2)CO_(3)(s) 2H^( )(aq)->2Na^( )(aq) H_(2)O(l) CO_(2)(g) B. Na_(2)CO_(3)(s) 2HClO_(4)(aq)->2NaClO_(4)(aq) H_(2)CO_(3)(g)
Which of the following statement is TRUE about X-ray diffraction (XRD)? Group of answer choices XRD is used to determine the crystal structure of a material based on the spacing between planes of atoms. XRD is used to heat treat a metal like iron, to get different crystal structures (bcc,fcc)
Question 1 options: Use the theoretical maximums to answer the following: How many electrons are needed to completely fill shell number 4 ? __1__ How many electrons are needed to completely fill shell number 5 ? __2__ A. 50 B. 5 C. 4 D. 40 E. 32 …
Consider the mixture of H2 and O2 in a closed container as illustrated by this box. What will the contents of this box look like if the molecules undergo this reaction? 2 H2 (g) + O2 (g) → 2 H2O (g)
Which of the following results in a decrease in the entropy of the system? Question 4 options: a) 2H2O2(g) → 2H2O(g) + O2(g) b) N2(g), 25°C → N2(aq), 25°C c) O2(g), 300 K → O2(g), 400 K d) NH3(l), –34.5°C → NH3(g), –34.5°C e) H2O(s), 0°C → H2O(l), 0°C
How do you select the ions to write in the net ionic equation? For example: NaCl(aq) + AgNO3(aq) ⟶ AgCl(s) + NaNO3(aq) Multiple Choice. Group of answer choices Locate the aqueous (aq) reactatnt Locate the solid (s) product Locate the solid (s) reactant Locate the aqueous (aq) product
Choose the item in column 2 that best matches each item in column 1. Match the following. 2 points each. 13) CH2F2 14) CH3OH 15) CH3CH3 16) LiI 17) LiI + H2O A) ionic bond B) dipole-dipole forces C) hydrogen bonding D) ion-dipole forces E) H2 + H2O F) dispersion forces
Orotic aciduria is characterized by an excess in orotic acid (at this point you should get your notes and find the synthetic pathway for pyrimidines). If you could give only one or two compounds to patients who suffer from orotic aciduria, which one would you choose? Justify your choice
Consider the boiling of water. At 1 bar, liquid and gas are in equilibrium 𝐺𝑚(𝑙) = 𝐺𝑚(𝑔). Calculate Delta Gm for increasing the pressure from 1.00 bar to 10.0 bar for (a) liquid water (𝜌 =0.9584 𝑔 𝑐𝑚−3); and (b) gaseous water vapor.
Is this sentence true of false? 1 point True, the frequency will be smaller for HCl than for DCl molecule. False, these frequencies will be equal. False, the DCl frequency will be smaller than HCl frequency. False, there is no way to solve this problem.
You have a mixture containing CH4, C2H6, CO 2, CO, H2O, and O2. How many independent reactions are needed to describe the system at equilibrium? How many would be needed if there is also elemental carbon in the system (i.e., mixture is CH4, C2H6, CO 2, CO, H2O, O2, and C)?
The combustion 1.0g sucrose in a bomb calorimeter causes the temperature to rise from 25◦C to 28◦C. the heat capacity of the calorimeter assembly is 4.90kj/◦C. what is the heat of the combustion of sucrose in (kj/mol) the molar mass of sucrose is 343 g/mol
When an electron in an unknown atom transitions from the n=3 to n=1 energy state, which statement correctly describes how the kinetic energy (KE), and potential energy (PE) of the excited electron changes in response to this transition to the n=1 energy state?
Read the following statement and select the matching gas law: For a confined gas, the volume (V) and number of moles (n) are directly proportional if the pressure and temperature both remain constant. Group of answer choices Amontons’s law Boyle’s law Avogadro’s law Ideal gas law Charles’s law
What is true for the following reaction at equilibrium? HF(aq) ⇄ H+(aq) + F-(aq) K=6.3 × 10-4 A. There will mostly be reactants B. There will mostly be products C. There will be an equal amount of products and reactants D. Nobody knows, it is too early in the morning for this crap!
Which rate equation correctly describes the reaction of sodium acetate with methyl bromide in acetic acid? Group of answer choices rate = k [sodium acetate] rate = k [acetic acid] [methyl bromide] rate = k [sodium acetate] [methyl bromide] rate = k [methyl bromide]
How does the rate constant change with increasing activation energy? 21 ANSWERS OPTIONS A As the activation energy increases, the rate constant (k) decreases. B As the activation energy increases, the rate constant (k) increases. C The rate constant is not affected by the activation energy.
Which of the reactions below is written in the direction “electron acceptor → electron donor”? a. FADH 2 → FAD + 2H + + 2e - b. Fe 2 + → Fe 3 + + e - c. ubiquinone + 2H + + 2e - → ubiquinone d. Glucose + H 2 O → CO 2 + 4H + + 4e - e. HS - → S ° + H + + 2e -
Calculate the pH at the points in the titration of 25.00 mL of 0.132 M HNO2 (Ka = 7.2 x 10-4 ) when: a) 10.00 mL of 0.116 M NaOH has been added [7 marks] b) 20.00 mL of 0.116 M NaOH has been added [8 marks]
What will the concentration of PCl5 be when equilibrium is reestablished after addition of 1.31 g Cl2? PCl5(g) ⇆ PCl3(g) + Cl2(g) Original Equilibrium Mixture: 3.03 g PCl5 4.86 g PCl3 3.59 g Cl2 in a 1.00-L flask. [PCl5] = mo(l)/(L)
What is the effect on pH when a buffer is diluted by a factor of 10? Group of answer choices The buffer pH deceases by 10. The buffer pH decreases by 1. The buffer pH decreases by 1. The buffer pH increases by 10. The buffer pH does not change appreciably.
Consider the following equilibrium: CaCO3(s)⇌Ca(aq)+2+CO3(aq)−2 Which of the following reagents, when added to the equilibrium system, would cause more CaCO3 to dissolve? Responses Na2CO3 (s) Na 2 CO 3 (s) H2C2O4 (s) H 2 C 2 O 4 (s) KNO3 (s) KNO 3 (s) CaCO3 (s)
10b. Explain the increase in successive ionization energies of Mg.Mg (g) ® Mg (g) e First ionization energy = 738 kJ mol-1Mg (g) ® Mg 2*(g) e Second ionization energy = 1451 kJ mol-1Mg 2*(g) ® Mg 3*(g) e Third ionization energy = 7733 kJ mol-1
If ammonia is added to a flask at room temperature the following equilibrium is established 2 NH3(g) <---> N2 (g) + 3 H2 (g) Kc =53 If the system is at equilibrium and more N2 is added to the container, which of the following is correct.
2. The reaction 2A (gas) → B (gas) is second order in A. For an initial pressure of A of 1 atm and B of 0atm, if the half-life of A is 1 hour, what are PA and PB at t = 1 hour and t = 2 hour?
Place the steps of the Nitrate test in the correct order: i. Add 20 drops of N,N-diethyl-1-naphthylamine ii. Inoculate organism into nitrate broth iii. Add 20 drops of sulfanilic acid iv. Add zinc if the test tube is not red ii, iii, i, iv iv, ii, i, iii iii, iv, i, ii i, ii, iii,…
(1pts) Experimental melting point of recovered 3-nitroaniline (°C) (2pts) Literature melting point of 3-nitroaniline (°C) (1pts) Does the melting point obtained for your product indicate that your sample is indeed 3-nitroaniline? Does your sample appear to be a mixture or pure?
The reaction that is described below is first order in both Y (green spheres) and Z (orange spheres): Y + Z → products Rate = k[Y][Z] If the volume in each vessel is the same, what are the relative rates of this reaction in (i) — (iv)?
Consider the following reaction with a two-step mechanism: Step 1: 2 NO2 → NO3 + NO (slow) Step 2: NO3 + CO → NO2 + CO2 (fast) Would the rate law change if the reaction occurred in a single step? If yes, what would be the new rate law?
Question 35.e of 38 Submit An unknown compound is processed using elemental analysis and found to contain 117.4 g of platinum, 28.91 g of carbon, and 33.71 g of nitrogen. The chemical formula of the compound is Pt(CN)₄. Provide the correct IUPAC name of the unknown compound.
in the dissociation steps of phosphoric acid, Identify and explain each equivalence point, describing when and why phosphate species gain or lose protons. Discuss the buffering capabilities of the system at each pKa.
When you do a Friedel-Crafts Alkylation with t-butyl alcohol, overaddition is not a problem. Why is this? Group of answer choices Because the t-butyl group rearranges. Because t-butyl is an EDG. Because of the steric bulk of the t-butyl group. Because t-butyl is an EWG.
All of the following species follow the octet rule. Which one would you expect to not be linear? HINT: Check your guides. Remember that there are many "linear" shapes that are associated with many classes of compounds (e.g. AB2, AB5, AB6). (SCN)- H2S HCN CO2
Place tube #3 in the water bath you prepared in step #1 for 8-10 minutes with periodic shaking. Describe any changes you observe in the solution. Did the addition of heat shift the equilibrium? If so, how did the shift effect the CO2+ ions?
Ammonium hydrogen sulfide (NH4SH) was detected in the atmosphere of Jupiter subsequent to its collision with the comet Shoemaker–Levy. The equilibrium between ammonia, hydrogen sulfide, and NH4SH is described by the following equation: $$NH4SH(s)NH3(g)+H2S(g)
16.21 Write equations showing how 2-phenylethanol could be prepared from each of the following starting materials: (a) Bromobenzene (b) Styrene (c) 2-Phenylethanal (C6H5 CH2CHO) (d) 2-Phenylethanoic acid (C6Hs CH2CO2H
cathodoluminescent phosphors are materials that emit colored light when struck by electrons. they are used in cathode ray tubes (in older TVs and computer monitors). The most common phosphors are composed of ZnS doped with a small amount of some other metal ion.
Glycerol and three fatty acids are bonded together through a condensation forming triglycerides. The bond formed between the fatty acids and the glycerol is called a(an) _____________. Question 14 options: hydrogen bond glycosidic bond peptide bond ester bond
What would happen if the concentration of either H2 or I2 was increased in an equilibrium system? A The forward reaction rate decreases. B The reverse reaction rate decreases. C The forward reaction rate increases. D No change happens in the reaction rates.
2HBr(g) H2(g) Br2(g)Hydrogen bromide, hydrogen, and bromine are at equilibrium at 8 atm. The pressure is decreased to 3 atm by increasing the volume. The system moves to establishes a new equilibrium. Which of the following statements are true?
The reaction that occurs between an amine and an acid is best illustrated by (CH3)2NH + HCl → (CH3)2NH + Cl-. (CH3)2NH + HCl → (CH3)2NH Cl- + H3O+. (CH3)2NH + HCl → (CH3)2NH2+ + OH-. (CH3)2NH + HCl → (CH3)2NH2 + Cl-. (CH3)2NH + H2O → (CH3)2N + H3O+.
3. When cyclohexanone is placed in 18O enriched water (1\deg OH,) and then recovered, it was found that the oxygen in the recovered cyclohexanone contained a significant amount of *O. Write a mechanism that explains this observation.
.Explain the most important nutritional role of carbohydrates and how they are created. Identify the basic structures of the major carbohydrates: monosaccharides, disaccharides, polysaccharides (e.g., starches), and fiber.
which of the following statements about mixed bonding is true? mixed bonding cannot occur in compounds that contain metals mixed bonding only occurs in organic molecules mixed bonding can result in materials with unique mechanical and electrical properties
An equilibrium is established for the reaction 2 CO(g) + MoO₂(s) ⇌ 2 CO₂(g) + Mo(s). Kp = 0.0111 and Q = 0.0245. Which way does the reaction need to shift to reach equilibrium? A forward B reverse C no shift is necessary, it is already at equilibrium.
2 Points) As an introduction to his class, Severus Snape teaches the first years at Hogwarts about hydrates. He begins with equations representing various dehydrations. Which of the following equations properly represents the dehydration of MgCO3·5H2O?
Casein does -----. Question 8 options: form the thick curd on top of milk (age gelation) by acid hydrolysis contain milk fat globule membrane make up less than 20 % of the total milk protein in a milk show good stability against heat denaturation
classify each characteristic as pertaining to atoms , elements , or both: 1.contain protons 2.the smallest amount of matter 3. a form of matter 4. defined by the number of protons they contain 5. substance composed of a single type of atom
The compound FeBr3 is an ionic compound where Fe (iron) has a positive charge. Using your understanding of ionic compounds, what is the correct positive charge for Fe (iron) Group of answer choices -3 cation -1 cation +1 cation. +3 cation. +8 cation
describe sodium borohydride. what are its properties? is it natural or made in a factory? describe sodium borohydride in relation to sodium hydride and lithium aluminum hydride. what are some similarities and differences
Small amounts of sugar solutions can be used as a minor analgesic for infants when given orally prior to mildly painful procedures, such as a heel prick for blood tests. How many grams of sucrose would you need to prepare 100 mL of a 24% sucrose solution?
Which of the species of the followinf pairs would you expect to have a larger, more positive, enthalpy of hydration, corresponting ti a less favored hydration A. Li+ or Na+ B. Rb+ or K+ C. Li+ or Cs+ D. Li+ or Be2+
One isotope of a metallic element has mass number 39 and has 20 neutrons in the nucleus. It forms an atomic ion having 18 electrons. Enter the symbol for this ion (give the symbol for the nucleus and give the ionic charge as a right superscript).
When using a separatory funnel containing two immiscible solvents, it is important to identify which solvent will be the top layer and which solvent will be the bottom layer. Which factor determines which layer rests on top and which rest on the bottom?
4.39 which of the folllowing paird has the higher boiling point explaina) Pentane or 2-methylbutane (b) Heptane or pentane (c) Propane or 2-chloropropane (d) Butane or 1-propanol (e) Butane or CH3COCH3
What is true for the following reaction at equilibrium? HF(aq) ⇄ H+(aq) + F-(aq) K=6.3 × 10-4 A. There will mostly be reactants B. There will mostly be products C. There will be an equal amount of products and reactants
Chemical Kinetics How will you collect data for this experiment? in-person Experiment 1 Exact concentration of H2O2 stock solution (M) 1.025 Temperature of water bath (°C) 21.0 Experiment 1: Volume of O2 vs time for decomposition of H2O2
If desflurane were accidentally put into a sevoflurane vaporizer, would the patient receive more or less anesthetic than intended? Explain your answer. The patient would receive more anesthetic since desflurane has a much Blank vapor pressure.
What solvent is used to elute the DNA? How do you think this differs from the composition of the wash buffers? Comment on the intermolecular forces between DNA and the wash buffer vs. DNA and the elution solvent.
Consider this overall reaction, which is experimentally observed to be second order in AB and zero order in C: AB + C ¡ A + BC Is the following mechanism valid for this reaction? AB + AB k ¡ 1 AB2 + A Slow AB2 + C k ¡ 2 AB + BC Fast
As the eluent moves the mixture through the column, it is collected in separate containers, known as fractions, at the bottom of the column. Why is it important that the eluent is collected in separate fractions rather than all in the same flask?
Decide if each item describes either covalent, ionic or hydrogen bonding. Note: you may use some terms more than once An atom of hydrogen has on eelectron in its first shell. one more electron is needed to fill this shell. In a molecule of H2,
Suppose that the half-life of steroids taken by an athlete is 35 days. Assuming that the steroids biodegrade by a first-order process, how long (in days) would it take for 164 of the initial dose to remain in the athlete's body?
When dicarboxylic acids (compounds with two –COOH groups in their structures) melt, they frequently decompose to produce 2 moles of CO2 gas for every 1 mole of dicarboxylic acid melted: $$HOOC(CH2)nCOOH(s)H(CH2)nH(l)+2CO2(l)
Indicate the reagents that would be used to resolve the following, discuss the reactions involved and specify the physical method that would be the best to separate the diastereomers of 2,3-pentadienedioic acid.
Enzymes typically work in very particular conditions. Under what conditions should pepsin work best? Low temperatures and high pH High temperatures and high pH Basic and acidic environments High temperatures and low pH
An element has the electron configuration 1s22s22p4 . For reactions that involve electron transfer, this element will likely? Group of answer choices Gain 2 electrons Gain 6 electrons Lose 6 electrons Be non-reactive Lose 2 electrons
Given the atomic number and atomic mass of element, determine the number of protons, the number of electrons (When the atom has no net charge), the electron configuration, and whether the atom is reactive or inert.
in part A.3 The dispensing of the edta solution is discontinued when the color turns to purple. Because of this technique error, will the calculated molarity of the edta A solution be too high, too low, or unaffected? explain
Which of the following formulas is (are) INCORRECT? rate x part = total rate x total = part part divided by total = rate part divided by rate = total total divided by rate = part both a and e. both b and e. both c and d.
1. Balance the following oxidation reactions by adding the appropriate components (be sure to include the e-). a. FeS2 ↔ Fe(OH)3 b. 2Cr3+ ↔ Cr2O72- c. Fe3O4 ↔ Fe2O3 d. ZnS ↔ ZnO + S
Which of the following reactions will be the fastest? Assume that the collision factors for the reactions are equal. 20 ANSWERS OPTIONS A Ea = 100 kJ/mol B Ea = 70 kJ/mol C Ea = 50 kJ/mol D The three reactions will have the same rate.
Which of the following ionic compounds is incorrectly named ? Group of answer choices (NH4)2SO3, ammonium sulfite PbO2, lead(II) oxide Ca3(PO4)2, calcium phosphate Cu2S, copper(I) sulfide Fe2O3, iron(III) oxide
step 1: H2O2 + I- to H2O + IO- step 2: H2O2 + IO- to H2O + O2 + I-. write out the rate law for each fundamental step and determine the molecularity for each step. identify the catalyst and intermediate of the reactions
The following reaction is at equilibrium at one atmosphere, in a closed container. Which, if any, of the following actions will decrease the total amount of CO2 gas present at equilibrium? NaOH(s) + CO2(g) ⟷ NaHCO3(s)
Consider the following spectrum. The compound used to generate this spectrum might have which of the following molecular formulas? C_(7)H_(16) C_(7)H_(16)O C_(7)H_(14) C_(7)H_(12) either C_(7)H_(14) or C_(7)H_(12)
Compound 2 is a light gray solid made of overlapping hexagonal crystals. When heated gently it starts to soften and develop an unpleasant smell about 50°C . above room temperature. is it ionic, molecular or can't decide
A 0.0310 M solution of an organic acid has an [H+] of 5.50×10-4 M . Using the values above, calculate the pH of the solution. What is the percent ionization of the acid? Calculate the Ka value of the acid.
An irregular shape object has a mass of 32 oz. A graduated cylinder with and initial volume of 18.9 mL. After the object was dropped in the graduated cylinder, it had a volume of 75 mL. What is the density of object g/mL)?
What is the overall charge (+, 0, or –) for the following amino acids at a pH of 5.97? Glycine (pI = 5.97) Overall charge: +0– Cysteine (pI = 5.07) Overall charge: +0– Histidine (pI = 7.59) Overall charge: +0–
Which base will make ~100% enolate from a general ketone? (select all that apply) Group of answer choices No answer text provided. No answer text provided. NaOH NaH NaNH2 NaOCH3 (CH3)3COK LDA DMF H2O none of these
A student was provided an unknown carbohydrate and asked to classify the type of saccharide. Which one of the following tests should the student perform? Ninhydrin test Iodine test Potassium permanganate test Bromine test
Is 2-pyridone aromatic? No, aromatic hydrogens absorb at about 4.5 ppmYes, aromatic hydrogens absorb at about 4.5 ppmNo, aromatic hydrogens absorb at about 9.2 ppmYes, aromatic hydrogens absorb at about 7.2 ppm
Would the sign of ΔSΔS be + or −− for the following changes? Match the words in the left column to the appropriate blanks in the sentences on the right. ResetHelp negative positive When a stick of dynamite explodes, ΔSΔS is Blank
Which molecular formula is consistent with the following mass spectrum data? M+* at m/z= 108, relative height=61.5% (M+2)** at m/z= 110, relative height=61.3% • C-H12 Cl O C2H,Br O C2H5Br • none of these • CgH12
A proposed mechanism has the following steps: Step 1: Ag+(aq) + Ce4+(aq) ↔ Ag2+(aq) + Ce3+(aq) Step 2: Tl+(aq) + Ag2+(aq) → Tl2+(aq) + Ag+(aq) Step 3: Tl2+(aq) + Ce4+(aq) → Tl3+(aq) + Ce3+(aq) What is the catalyst?
Solve each of the conversions below. Do not include units in the answers to this problem. A. 326.75 K = __________ degC. B. -146.2 degC = __________ K. C. 1054.65 K = __________ degC. D. 73 degC = __________ K
When added to uranyl solutions, magnesia MgO can precipitate uranium as a hydrated uranium trioxide UO3 · xH2 O. Write a balanced equation for this reaction. (Hint: MgO is converted to Mg2+ .)
The boiling point of cycloheptane is 118.5°C. Its constitutional isomer, 1,1-dimethylcyclopentane, has a boiling point of only 87.5°C. Explain the difference in the boiling points of these two C7H14 compounds.
How many years would it take for 4 grams of Carbon-14 to decay to 0.25 grams? (Recall: C-14 has a half-life of 5730 years). Question 18 options: 17 190 years 22 920 years none of the choices 5730 years 4 years
Solvents with very low boiling points, such as diethyl ether, can create pressure inside the separatory funnel as a result of shaking. The funnel should be immediately vented after shaking/mixing. True False Clear selection
Consider the rate law rate=k[A]^n [B]^m When the concentration of reactant A increases by a factor of 3.0 the initial rate of reaction increases by a factor of 1.0. What is the order of reaction for reactant A?
Which of the following coordination compounds will form a precipitate when treated with an aqueous solution of AgNO3? Group of answer choices [Cr(NH3)3Cl3] [Cr(NH3)6]Cl3 Na3[Cr(CN)6] all of these Na3[CrCl6]
Which of the following will result from the addition of a catalyst to a reaction? I. increases the rate of the reaction II. decreases the activation energy III. increases the value of k (rate constant)
Write the equilibrium constant expressions for K and Kp for the following equilibrium reaction. 2ZnS(s) + 3O2(g) ⇔ 2ZnO(s) + 2SO2(g) (Enter K= answer and Kp=answer on the same line with a space between them)
match each term with it's definition. the position of an equilibrium always shifts in such a direction as to relieve a stress applied to the system. A molecule that donates a proton when it encounters a proton acceptor.
Which of the following types of probe detection develops color on the blot itself and thus only allows one exposure to be obtained? Group of answer choices chromogenic chemifluorescent radioactive chemiluminescent
Hydrogen peroxide decomposes spontaneously to yield water and oxygen gas according to the reaction equation 2H2O2 (aq) --> 2H2O(l) + O2 (g) The activation energy for this reaction is 75 kJ mol^-1. The enzyme catalase
Consider the following four formulas: SO3SO3, B2H6B2H6, COCO, C4H4O2C4H4O2. Which of these formulas could be only an empirical formula, only a molecular formula, either a molecular or an empirical formula?
What type(s) of intermolecular forces are present between sodium chloride and ammonia? Question 3Select one or more: A. ion-dipole B. dispersion C. dipole-dipole D. ion-induced dipole E. dipole-induced dipole
Identify and explain each equivalence point, describing when and why phosphate species gain or lose protons. Discuss the buffering capabilities of the system at each pKa.
If your initial mixture had contained two compounds containing a carbonic acid and one containing an amine, would you expect to be able to separate the three compounds using this form of extraction?
The following step of radical halogenation of alkanes is characterized by the formation of alkyl radicals by the removal of hydrogen atoms. As a consequence, hydrohalic acids like HCl and HBr are also formed.
Measure 30mL of 1M CuSO4 in the 50mL graduated cylinder. Calculate the stoichiometric amount of aluminum foil needed to completely react to your CuSO4. Please use dimensional anaylsis to show work.
chlorine can be prepared in the laboratory by the reaction of maganese dioxide with hydrochloric acid HCl(aq) as described by the chemical equation MnO2(s) + 4 HCl(aq) - MnCl2(aq) + 2H2O(l) + Cl2(g)
1) What are some examples of colloids you would find in nature or your body? 2) What are their roles? 3) What are some examples of manmade colloids? Gel 4) How do they compare to naturally occurring colloids?
Aqueous solutions of acetic acid and barium hydroxide can neutralize each other to produce a compound that is soluble in water. Identify the chemical formulas of the anion and cation found in this compound.
Which of the following is a COMBINATION reaction? 2 NaCl(aq) + CaO(aq) → Na2O(aq) + CaCl2(aq) 2 NaClO3(s) → 2 NaCl(s) + 3 O2(g) 4 NaCl(s) + O2(g) → 2 Na2O(s) + 2 Cl2(g) 2 NaCl(s) + 3 O2(g) → 2 NaClO3(s)
Complete and balance the following equation for the reaction of Bi (bismuth) with excess Br2. Assume that Bi adopts its most common oxidation state. Include the physical states of reactants and products.
In part B.1. a student forgot to polish the magnesium metal which had evidence of rust on it. As a result of this error the reported magnesium to oxygen ratio will be ___________. too high unaffected too low
Which of the following solutions is the most basic? (i) 0.0025 M NaOH (ii) H2O (iii) 0.0025 M HI (iv) 0.005 M Ca(OH)2 (v) 0.005 M KOH Group of answer choices (i) (iii) (ii) (iv) (v)
Which of the following is paramagnetic? Group of answer choices [Mn(CN)6]4– (strong field) [Co(NH3)6]3+ (strong field) [Zn(H2O)6]2+ [Fe(CN)6]4– (strong field) [Cu(en)3]+
Explain how changing the reaction temperature effected the equilibrium of the cobalt (II) complex system. In which direction did the equilibrium shift when you decreased the reaction temperature?
drawn the amino acids arginine, lysine, aspartate, and glutamate at pH 1, 7, and 13, and state the charge of each amino acid at each pH. This means you will draw 12 structures.
Consider an equation s = 2.15t2 + 0.1421t + 1.260. Find the value of s rounded to the proper number of significant digits, if t = 3.7. Instruction: enter your response rounded to two significant digits. s =
which of the following is a true statement: metallic elements donate electrons while non-metalllic elements receive elecrons, metallic elements receive electrons while non-metallic elements donate electrons
If you initial mixture had contained two compounds containing carbon silk acids, and one containing in a mean, would you expect to be able to separate the three compounds using this form extraction?
Examine the biochemical reaction below: CH3CH2OH + NAD+ ↔ CH3CHO + NADH + H+ Which of the following products results from an oxidation of the substrate in the above reaction? EtOHNAD+NADHAcetaldehyde
A student sets up the following equation to convert a measurement. (The ? stands for a number the student is going to calculate.) Fill in the missing part of this equation. ⋅×−6.9103Ncm=?Nmm
Which is not the correct chemical formula for the compound named? Group of answer choices sodium carbonate, Na2CO3 phosphoric acid, H3PO4 nitric acid, HNO3 copper(II) nitrate, CuNO2 iron(III) oxide, Fe2O3
What is the expression for the rate law for the racemization process? Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a Your answer b c d
Based on their intermolecular forces, polarity and other physical characteristics, rank the solvents from highest to lowest ΔHvap: 1-butanol , 2-butanol , Cyclohexane , Ethyl acetate
Osmolality refers to milliosmoles of ions and molecules per _____ Group of answer choices kilogram of solvent (mOsm/kg) liter of solvent (mOsm/L) kilogram of solution (mOsm/kg) liter of solution (mOsm/L)
4. (5 pts) Will the linoleic acid in the soybean oil that you may consume be converted to glucose with a net yield in your liver? _________ Defend you answer by showing pertinent reactins. Yes or No
Two molecules, one linear and one non‐linear, that have the same number of atoms (N), will have the same number of normal modes.
For any pair of enantiomers, one enantiomer is dextrorotatory, and the other is levorotatory. For each member, the value of the specific rotation is exactly the same, but the sign is the opposite.
The linear equation also contains the value of k the pseudo-order rate constant for part 1 including units. Replace the units of absorbance with the concentration of the bromophenol blue
The addition of an alcohol to an acid chloride is an example of alcoholysis (alcohol addition with bond breakage). Consider the alcoholysis reaction below and answer the questions that follow.
In polar aprotic solvent, F- is a [ Select ] ["better", "worse"] nucleophile than I-. In polar protic solvent, F- is a [ Select ] ["worse", "better"] nucleophile than I-.
1) Based on your experience of the solubility of aniline in neutral water vs. in acidic hydrochloric acid, explain why most amine drugs are formulated as an acid salt instead of an amine?
Which of the following is true? i. The pH of a neutral solution is always 7.0. ii. For a neutral solution [H⁺] = [OH⁻]. Question 7 options: 1) i only 2) ii only 3) both i and ii 4) neither i or ii
A 25.00 mL solution of 0.08530 M NaI is titrated with 0.05030 M AgNO3. Given the 𝐾sp of AgI is 8.3×10^−17. When 24 mL of AgNO3 is added, calculate pAg+.
At pH 4.6, casein is (has) ______________________________. Question 29 options: net negative charge net positive charge maximum Interaction between two protein molecules maximum solubility
Define halogenation of an alkene. • It is the addition of HCl to the alkene. It is the addition of Cl to the alkene. It is the addition of H2O to the alkene. It is the addition of H2 to the alkene.
27. Double bonds can also act like Lewis bases, sharing their electrons with Lewis acids. Use curved arrows to show how each double bond below will react with HCl and draw the resulting
Molecules with NO plane of symmetry are chiral. Identify which of the following molecules are chiral. A Compound 1 B Compounds 1 and 2 C Compound 2 D Compounds 2 and 4 E Compound 4
In each case tell which SN2 reaction will proceed faster. 1. The displacement by I- on (a) CH3Cl or (b) CH3OTos. ab 2. The displacement on 1-iodopropane of (a) CH3O- or (b) CH3CO2-
The ΔG of the following reaction is –2.8 kcal/mol: acetyl phosphate + ADP ↔ acetate + ATPIs ADP greater than, lesser than, or equal to acetate in its affinity for phosphate? (4 marks)
Enter an abbreviated electron configuration for manganese: Express your answer in complete form, in order of increasing energy. For example, [He]2s22p2 would be entered as [He]2s^22p^2.
To convert mass of an atom in grams to moles you must divide by? Select the correct answer below: Planck's constant The number of electrons in the atom The molar mass Avogadro’s number
200 mg = __________ g 1.5 g = ____________ mg 15 L = ____________mL 2 tsp = ___________ mL ½ oz = __________ Tbs 2 Tbs = __________mL 2500 mL = _______ L
Match the electron structure below with the element type it represents.1s22s22p63s23p64s1 Group of answer choices Halogen Alkaline earth metal Alkali metal Inert gas Transition metal
What is the sum of these contributions? Report your answer to two decimal places. Mass contribution of 24Mg = 18.946 amu Mass contribution of 25Mg = 2.499 amu Mass contribution of 26Mg = 2.861 amu
Write the equilibrium constant expression Kia for the dissociation of acetic acid and the quilibrium constant expression for the dissociation of sodium acetate in
Describe all the steps of the radical halogenation mechanism Propane (CH3CH2CH3) with molecular chlorine (Cl2) (propose possible racemic mixture) (p. 255)
Which of the following carboxylic acid derivatives could be used in this forward reaction? X = Br X = Cl X = SCH3 X = OCH3 X = OH -OH is stronger base than the amide Question 6
During an extraction, if you become uncertain about which layer is the organic layer (and you don’t know the exact density of the solvents), what would you do to determine it experimentally
The signal at 1740 cm-1 in the IR spectrum of methyl 3-nitrobenzoate is due to what functional group? Question 1 options: the aromatic ring the ester group the methyl group the nitro group
Complete the following sentence: Osmosis is the passage of __________molecules from a _________ concentrated solution to a ___________concentrated solution through a _____________________
When some substances are dissolved in water, they undergo either a physical or a chemical change that yields ions in solution. These substances constitute an important class of compounds called
Suppose a 40. L reaction vessel is filled with 1.4 mol of NO and 1.4 mol of CO2. What can you say about the composition of the mixture in the vessel at equilibrium?
For each pound of _____ that enters surface water ________ pounds of algae can be the result. Question 27 options: K 1000 H 100 No2- 10 P 1000
What is the ground-state electronic configuration of a chlorine anion (Cl–)? Select one: A. 1s2, 2s2, 2p6, 3s2, 3p4 B. 1s2, 2s2, 2p6 C. 1s2, 2s2, 2p6, 3s2, 3p6 D. 1s2, 2s2, 2p6, 3s2, 3p5
Draw the structures of the six bromoalkenes with the molecular formula C5H9Br that have a branched carbon chain, and that show neither E,Z isomerism nor chirality.
Given that N2H4 + 2H2O2 yields N2 + 4(H20) and you have 6 mol of N2H4 and 4.5 mol of H2O2, why is one of the byproducts N2 in grams 2.25 times its molar weight ?
What is the freezing point of water made by dissolving 17.63 g of magnesium chloride in 92.40 g of water? The freezing-point depression constant of water is 1.86 oC/m.
enzymnes use several types of catalytic mechanisms. Classify each description as characteristic of acid-base catalysis, covalent catalysis,metal ion catalysis, or all three m echanims
Explain why the addition of solid calcium chloride resulted in an equilibrium shift toward the left, while the addition of solid calcium nitrate had no effect on the equilibrium.
Sucrose is hydrolyzed to give the following two monosaccharides. Which monosaccharide can be directly oxidized by Cu2+? Question 3 options: Both 1 and 2 Neither 1 only 2 only
Which of the following reactions describes the process of reducing silver to its visible metallic state without the aid of extraneous agents? argentaffin decidual argyrofilic luteinizing
Compare acidity of following metal ions when dissolved in water (same concentration and same counter anion): Ca2+, Rb+, Sr2+, Sc3+. Which of the following conclusion is wrong?
The reactant concentration in a first-order reaction was 7.40×10−2 M after 25.0 s and 6.80×10−3 M after 90.0 s . What is the rate constant for this reaction?
Some facts about the ethylene molecule:number of carbon-carbon single (C - C) bonds: 2 number of carbon-hydrogen single (C - H) bonds: 2 number of carbon-carbon double (C = C) bonds:
Which of the following ions does NOT have the same number of valence electrons as neon? Group of answer choices magnesium ion calcium ion sodium ion oxide ion fluoride ion
Alkyl Halides Methyl cyclobutene can react withHX (hydrogen halides) in an electrophilic addition reaction to form alkyl halides. Example: Reaction with HBr → Bromo-methyl cyclobutane.
2-57. Draw as many resonance structures as you can for the following species, adding appropriate formal charges to each: a. Nitromethane b. Ozone c. Diazomethne
From your predicted value of the van't Hoff factor, calculate the boiling point of a 1.60 m aqueous solution of barium nitrate, Ba(NO3)2. The Kb of water is 0.52°C/m.
n which of these gas-phase equilibria is the yield of products increased by increasing the total pressure on the reaction mixture? Group of answer choices 2NO(g) + Cl2(g) ⟷ 2NOCl(g) 2H2O2 (g) ⟷ 2H2O(g) + O2(g) 2SO3(g) ⟷ 2SO2(g) + O2(g) PCl5(g) ⟷ PCl3(g) + Cl2(g) CO(g) + H2O(g) ⟷ CO2(g) + H2(g)
(2) Carbon monoxide and chlorine combine in an eq reaction to produce the highly toxic product phosgene (cocle) If the eq constant for this reaction is K_(c)=248, predict, if possible what will happen when the reactants and products are combined The reaction will proceed to the right The…
Question 11Which of the following statements is typically true for a catalyst?1. The concentration of the catalyst will go down as a reaction proceeds./1. The catalyst provides a new pathway in the reaction mechanism.IlI. The catalyst speeds up the reaction. a. I only O b. I and III O c. Il…
The following process may take place in three steps: 2 ClO (g) 2 Cl (g) + O2 (g) S1: 2 ClO (g) ClOOCl (g) S2: ClOOCl (g) ClOO (g) + Cl (g) S3: ClOO (g) Cl (g) + O2 (g) The rate law for this process has been experimentally determined to be Rate = k[ClO]2. Based off this…
If the superanatant liquid is tested with barium chloride, what does this tell you about the reaction? Group of answer choices If a precipitate is formed Cobalt is in excess If a precipitate is formed Carbonate is in excess If a precipitate is formed barium is in excess If a precipitate is…
13. A student measures the pH of a water-based solution to be 8. After the addition of a small amount of a different substance, the pH of the solution increases to 9.a. Did the student add an acid or a base to the solution? Explain your answer.b. Describe what happened to the solution in the…
Question 10 / 1 point When the following pairs of solutions are mixed, which produces the strongest electrolyte solution? Question options: Pb(CH3COO)2 (1 M) + NaI (2 M) Ba(OH)2 (3 M) + CuSO4 (3 M) Zn(NO3)2 (1 M) + AgClO4 (2 M) HCl (2 M) + NaOH (2 M) KCl (1 M) + NH4NO3 (1 M)
In a 0.18mM aqueous solution of trimethylacetic acid C4H9CO2H , what is the percentage of trimethylacetic acid that is dissociated? You can find some data that is useful for solving this problem in the ALEKS Data resource. Round your answer to 2 significant digits.
125I is an isotope used in nuclear medicine and commonly produced by McMaster University in a radioactive concentration of 1014. mCi/mL (Ci, or Curie is a unit of measure of radioactivity). If the half life of 125I is 59.6 days, after production and delivery, requiring 10. days, what would be…
in the context of metallic bonding, what is the "electron sea" model? a model describing the sharing of electron pairs between atoms a model where valence electrons move freely among metal cations, creating a "sea" of electrons a model where electrons are fixed in position with a lattice a…
A bottle of allyl bromide was found to contain a large amount of an impurity. A careful distillation separated the impurity, which has the molecular formula C3H6OC3H6O. The following 13C13C NMR spectrum of the impurity was obtained: Assign the peaks in the 13C13C NMR spectrum to the carbon…
Constitutional isomers are molecules which have the same molecular formula but have different connectivities - or the order they are put together. There are three categories of constitutional isomers: skeletal, positional, and functional isomers. Positional isomers are also called? Group of…
Question 9 (1 point) Saved The law of conservation of matter refers to the fact that Question 9 options: coefficients or subscripts can be changed when balancing a chemical reaction. atoms cannot appear or disappear. in certain cases, matter can be converted to energy. the mass you start with…
Using the mechanism below, what would be the appropriate equilibrium constant expression for the overall reaction? Step 1: 2 Br-(aq) + H2O2(aq) + 2 H+(aq) à Br2(aq) + 2 H2O(l) slow Step 2: Br2(aq) + H2O2(aq) ßà 2 Br-(aq) + 2 H+(aq) + O2(g) fast
The standard Gibbs free energy change for hydrolysis of pure ATP to pure ADP is -31 kJ/mol. The reaction is written [ATP] ↔ [ADP] + [Pi]. What is the Gibbs energy of reaction in an environment at 37 °C in which the ATP, ADP, and Pi concentrations are all 1 mmol/L or 1 μmol/L? (Atkins 4.14)
Suppose your car’s radiator system contains 1.50L of water. How many liters of antifreeze, ethylene glycol (C2H6O2), would you add to the water in your radiator to keep it from freezing if the coldest winter temperature in your area is -25.0oC? (NOTE: The density of ethylene glycol is 1.1135…
Which of the following would be the oxygen pressure entering and leaving this capillary? entering Po2 40 mm Hg, leaving Po2 100 mm Hg entering Po2 40 mm Hg, leaving Po2 45 mm Hg entering Po2 95 mm Hg, leaving Po2 40 mm Hg entering…
galactose is metabolized by a pathway that includes the isomerization of UDP-galactose to UDP-glucose, where UDP = urdylyl diphosphate. curved a are used to illustrate the flow of electrons-pushing arrows for the reaction. uridyl is abbreviated as R. be sure the account for all bond breaking…
Using the tests described in this experiment, how could one distinguish between the following pairs of compounds? Tell what reagent or test you would use and what you would see. a. 1-butanol and 2-butanol b. isobutyl alcohol and rert-butyl alcohol c. 1-propanol and 1-heptanol d. cyclohexanol…
When doing an equilibrium problem based on the following reaction and assuming your initial concentration is 2.0 M, what approximation can you make? HF(aq) ⇄ H+(aq) + F-(aq) K=6.3 × 10-4 2.0 0 0 -x +x +x 2.0-x x x A. x is zero B. x is negligible…
A hypothetical ceramic, Virginium Sulfide (VrS) has a density of 4.306 g/cm3 and cubic unit cell with a cell edge length of 0.512 nm. In addition, we know that: Atomic Wt.: Vr 54.94 g/mol; S 32.06 g/mol Radii: Vr: 0.122 nm; Vr+2: 0.072; S: 0.106 nm; S-2: 0.184 Electronegativity: Vr 1.5; S 2.5…
Question 8Equilibrium is reached in chemical reactions when: a. The forward reaction stops. b. The concentrations of reactants and products become equal. c. The temperature shows a sharp rise.O d. The rates of the forward and reverse reactions become equal.O e. All chemical reactions stop.A…
Two atoms S and O approach each other. The S atom has the following energies of atomic orbitals 1s=-50.1 a.u. ; 2s =-30.5 a.u; 2p=-15.6 a.u; 3s=-10.8 a.u; 3p=-5.2 a.u. The O atom has the following energies of atomic orbitals 1s=-22.1 a.u. ; 2s =-12.5 a.u; 2p=-4.3 a.u. Based on this information,…
Microbes have been found to thrive in which of the following hostile conditions? Select all that apply. Group of answer choices sterilizing radiation 200 atm pressure astroids in deep space above the boiling point of water below the freezing point of water molten lava brine of 30% salt
Why are EDTA specimens obtained before other specimens when collected by dermal puncture? To minimize the effects of platelet clumping. To minimize tissue fluid contamination. To prevent contamination from carryover. EDTA are not collected first. The order of the draw is no different for dermal…
1. Obtain a 50-mL beaker. To determine the mass of the empty beaker, go to a balance, and press the “Tare” or “Zero” button and wait until the digital display reads 0 g. Place the beaker on the balance and record the mass given by the display after it stabilizes. Remember to record all of the…
A 0.580 M Nitrous Acid (HNO2) solution has been mixed with 0.050 M NaCl. What will be the hydronium ion concentration of this solution? The activity coefficients for H3O+ and NO2− are 0.86 and 0.80 respectively. The Ka for Nitrous Acid is 5.10000×10-4.
First ionization energies tend to increase across a period. But in period 2, Be has a higher first ionization energy than B, and N has a higher first ionization energy than O. Explain. [Hint: Look at the valence configurations, and recall that half-filled and fully filled subshells have…
Consider the following reaction: A+B+C→D The rate law for this reaction is as follows: Rate=k[A][C]2[B]1/2 Suppose the rate of the reaction at certain initial concentrations of A, B, and C is 1.11×10−2 M/s .
How much of Clancy's favorite vintage (12% w/w ethanol) must he consume in order to lower the activity of his ADH on methanol to 5% of its normal value if the K_m values of canine ADH for ethanol and methanol are 1 millimolar and 10 millimolar, respectively?
Write out the entire sequence of dissociation reactions starting from H3PO4 to PO43- . Explain equivalence points, where and why species are protonated and deprotonated, and address their buffering capabilities.
What is true about the mass spectrum below? ◻ contains a hydroxyl fragment could be the mass spectrum for 2,2-dimethylheptane could be the mass spectrum for 2,2,3-trimethylpentane could be the mass spectrum for pentane Contains a CH_(2)CH_(3) fragment could be the mass spectrum for cyclohexane
Which of the following sets of quantum numbers represent valid sets? EXPLAIN what is wrong with the ones that are not valid. a. (3, 3, 0, -1/2) b. (2, 1, 0, 1/2) c. (6, 5, -1, 1/2) d. (6, 4, 2, 1) e. (4, 3, 4, -1/2) f. (3, 2, 1, 1/2)
What is the net ionic equation for the reaction of dilute perchloric acid (HClO_(4)) with solid sodium carbonate to produce a gas and colorless solution? A. Na_(2)CO_(3)(s) 2H^( )(aq)->2Na^( )(aq) H_(2)O(l) CO_(2)(g) B. Na_(2)CO_(3)(s) 2HClO_(4)(aq)->2NaClO_(4)(aq) H_(2)CO_(3)(g)
Which of the following statement is TRUE about X-ray diffraction (XRD)? Group of answer choices XRD is used to determine the crystal structure of a material based on the spacing between planes of atoms. XRD is used to heat treat a metal like iron, to get different crystal structures (bcc,fcc)
Question 1 options: Use the theoretical maximums to answer the following: How many electrons are needed to completely fill shell number 4 ? __1__ How many electrons are needed to completely fill shell number 5 ? __2__ A. 50 B. 5 C. 4 D. 40 E. 32 …
Consider the mixture of H2 and O2 in a closed container as illustrated by this box. What will the contents of this box look like if the molecules undergo this reaction? 2 H2 (g) + O2 (g) → 2 H2O (g)
Which of the following results in a decrease in the entropy of the system? Question 4 options: a) 2H2O2(g) → 2H2O(g) + O2(g) b) N2(g), 25°C → N2(aq), 25°C c) O2(g), 300 K → O2(g), 400 K d) NH3(l), –34.5°C → NH3(g), –34.5°C e) H2O(s), 0°C → H2O(l), 0°C
How do you select the ions to write in the net ionic equation? For example: NaCl(aq) + AgNO3(aq) ⟶ AgCl(s) + NaNO3(aq) Multiple Choice. Group of answer choices Locate the aqueous (aq) reactatnt Locate the solid (s) product Locate the solid (s) reactant Locate the aqueous (aq) product
Choose the item in column 2 that best matches each item in column 1. Match the following. 2 points each. 13) CH2F2 14) CH3OH 15) CH3CH3 16) LiI 17) LiI + H2O A) ionic bond B) dipole-dipole forces C) hydrogen bonding D) ion-dipole forces E) H2 + H2O F) dispersion forces
Orotic aciduria is characterized by an excess in orotic acid (at this point you should get your notes and find the synthetic pathway for pyrimidines). If you could give only one or two compounds to patients who suffer from orotic aciduria, which one would you choose? Justify your choice
Consider the boiling of water. At 1 bar, liquid and gas are in equilibrium 𝐺𝑚(𝑙) = 𝐺𝑚(𝑔). Calculate Delta Gm for increasing the pressure from 1.00 bar to 10.0 bar for (a) liquid water (𝜌 =0.9584 𝑔 𝑐𝑚−3); and (b) gaseous water vapor.
Is this sentence true of false? 1 point True, the frequency will be smaller for HCl than for DCl molecule. False, these frequencies will be equal. False, the DCl frequency will be smaller than HCl frequency. False, there is no way to solve this problem.
You have a mixture containing CH4, C2H6, CO 2, CO, H2O, and O2. How many independent reactions are needed to describe the system at equilibrium? How many would be needed if there is also elemental carbon in the system (i.e., mixture is CH4, C2H6, CO 2, CO, H2O, O2, and C)?
The combustion 1.0g sucrose in a bomb calorimeter causes the temperature to rise from 25◦C to 28◦C. the heat capacity of the calorimeter assembly is 4.90kj/◦C. what is the heat of the combustion of sucrose in (kj/mol) the molar mass of sucrose is 343 g/mol
When an electron in an unknown atom transitions from the n=3 to n=1 energy state, which statement correctly describes how the kinetic energy (KE), and potential energy (PE) of the excited electron changes in response to this transition to the n=1 energy state?
Read the following statement and select the matching gas law: For a confined gas, the volume (V) and number of moles (n) are directly proportional if the pressure and temperature both remain constant. Group of answer choices Amontons’s law Boyle’s law Avogadro’s law Ideal gas law Charles’s law
What is true for the following reaction at equilibrium? HF(aq) ⇄ H+(aq) + F-(aq) K=6.3 × 10-4 A. There will mostly be reactants B. There will mostly be products C. There will be an equal amount of products and reactants D. Nobody knows, it is too early in the morning for this crap!
Which rate equation correctly describes the reaction of sodium acetate with methyl bromide in acetic acid? Group of answer choices rate = k [sodium acetate] rate = k [acetic acid] [methyl bromide] rate = k [sodium acetate] [methyl bromide] rate = k [methyl bromide]
How does the rate constant change with increasing activation energy? 21 ANSWERS OPTIONS A As the activation energy increases, the rate constant (k) decreases. B As the activation energy increases, the rate constant (k) increases. C The rate constant is not affected by the activation energy.
Which of the reactions below is written in the direction “electron acceptor → electron donor”? a. FADH 2 → FAD + 2H + + 2e - b. Fe 2 + → Fe 3 + + e - c. ubiquinone + 2H + + 2e - → ubiquinone d. Glucose + H 2 O → CO 2 + 4H + + 4e - e. HS - → S ° + H + + 2e -
Calculate the pH at the points in the titration of 25.00 mL of 0.132 M HNO2 (Ka = 7.2 x 10-4 ) when: a) 10.00 mL of 0.116 M NaOH has been added [7 marks] b) 20.00 mL of 0.116 M NaOH has been added [8 marks]
What will the concentration of PCl5 be when equilibrium is reestablished after addition of 1.31 g Cl2? PCl5(g) ⇆ PCl3(g) + Cl2(g) Original Equilibrium Mixture: 3.03 g PCl5 4.86 g PCl3 3.59 g Cl2 in a 1.00-L flask. [PCl5] = mo(l)/(L)
What is the effect on pH when a buffer is diluted by a factor of 10? Group of answer choices The buffer pH deceases by 10. The buffer pH decreases by 1. The buffer pH decreases by 1. The buffer pH increases by 10. The buffer pH does not change appreciably.
Consider the following equilibrium: CaCO3(s)⇌Ca(aq)+2+CO3(aq)−2 Which of the following reagents, when added to the equilibrium system, would cause more CaCO3 to dissolve? Responses Na2CO3 (s) Na 2 CO 3 (s) H2C2O4 (s) H 2 C 2 O 4 (s) KNO3 (s) KNO 3 (s) CaCO3 (s)
10b. Explain the increase in successive ionization energies of Mg.Mg (g) ® Mg (g) e First ionization energy = 738 kJ mol-1Mg (g) ® Mg 2*(g) e Second ionization energy = 1451 kJ mol-1Mg 2*(g) ® Mg 3*(g) e Third ionization energy = 7733 kJ mol-1
If ammonia is added to a flask at room temperature the following equilibrium is established 2 NH3(g) <---> N2 (g) + 3 H2 (g) Kc =53 If the system is at equilibrium and more N2 is added to the container, which of the following is correct.
2. The reaction 2A (gas) → B (gas) is second order in A. For an initial pressure of A of 1 atm and B of 0atm, if the half-life of A is 1 hour, what are PA and PB at t = 1 hour and t = 2 hour?
Place the steps of the Nitrate test in the correct order: i. Add 20 drops of N,N-diethyl-1-naphthylamine ii. Inoculate organism into nitrate broth iii. Add 20 drops of sulfanilic acid iv. Add zinc if the test tube is not red ii, iii, i, iv iv, ii, i, iii iii, iv, i, ii i, ii, iii,…
(1pts) Experimental melting point of recovered 3-nitroaniline (°C) (2pts) Literature melting point of 3-nitroaniline (°C) (1pts) Does the melting point obtained for your product indicate that your sample is indeed 3-nitroaniline? Does your sample appear to be a mixture or pure?
The reaction that is described below is first order in both Y (green spheres) and Z (orange spheres): Y + Z → products Rate = k[Y][Z] If the volume in each vessel is the same, what are the relative rates of this reaction in (i) — (iv)?
Consider the following reaction with a two-step mechanism: Step 1: 2 NO2 → NO3 + NO (slow) Step 2: NO3 + CO → NO2 + CO2 (fast) Would the rate law change if the reaction occurred in a single step? If yes, what would be the new rate law?
Question 35.e of 38 Submit An unknown compound is processed using elemental analysis and found to contain 117.4 g of platinum, 28.91 g of carbon, and 33.71 g of nitrogen. The chemical formula of the compound is Pt(CN)₄. Provide the correct IUPAC name of the unknown compound.
in the dissociation steps of phosphoric acid, Identify and explain each equivalence point, describing when and why phosphate species gain or lose protons. Discuss the buffering capabilities of the system at each pKa.
When you do a Friedel-Crafts Alkylation with t-butyl alcohol, overaddition is not a problem. Why is this? Group of answer choices Because the t-butyl group rearranges. Because t-butyl is an EDG. Because of the steric bulk of the t-butyl group. Because t-butyl is an EWG.
All of the following species follow the octet rule. Which one would you expect to not be linear? HINT: Check your guides. Remember that there are many "linear" shapes that are associated with many classes of compounds (e.g. AB2, AB5, AB6). (SCN)- H2S HCN CO2
Place tube #3 in the water bath you prepared in step #1 for 8-10 minutes with periodic shaking. Describe any changes you observe in the solution. Did the addition of heat shift the equilibrium? If so, how did the shift effect the CO2+ ions?
Ammonium hydrogen sulfide (NH4SH) was detected in the atmosphere of Jupiter subsequent to its collision with the comet Shoemaker–Levy. The equilibrium between ammonia, hydrogen sulfide, and NH4SH is described by the following equation: $$NH4SH(s)NH3(g)+H2S(g)
16.21 Write equations showing how 2-phenylethanol could be prepared from each of the following starting materials: (a) Bromobenzene (b) Styrene (c) 2-Phenylethanal (C6H5 CH2CHO) (d) 2-Phenylethanoic acid (C6Hs CH2CO2H
cathodoluminescent phosphors are materials that emit colored light when struck by electrons. they are used in cathode ray tubes (in older TVs and computer monitors). The most common phosphors are composed of ZnS doped with a small amount of some other metal ion.
Glycerol and three fatty acids are bonded together through a condensation forming triglycerides. The bond formed between the fatty acids and the glycerol is called a(an) _____________. Question 14 options: hydrogen bond glycosidic bond peptide bond ester bond
What would happen if the concentration of either H2 or I2 was increased in an equilibrium system? A The forward reaction rate decreases. B The reverse reaction rate decreases. C The forward reaction rate increases. D No change happens in the reaction rates.
2HBr(g) H2(g) Br2(g)Hydrogen bromide, hydrogen, and bromine are at equilibrium at 8 atm. The pressure is decreased to 3 atm by increasing the volume. The system moves to establishes a new equilibrium. Which of the following statements are true?
The reaction that occurs between an amine and an acid is best illustrated by (CH3)2NH + HCl → (CH3)2NH + Cl-. (CH3)2NH + HCl → (CH3)2NH Cl- + H3O+. (CH3)2NH + HCl → (CH3)2NH2+ + OH-. (CH3)2NH + HCl → (CH3)2NH2 + Cl-. (CH3)2NH + H2O → (CH3)2N + H3O+.
3. When cyclohexanone is placed in 18O enriched water (1\deg OH,) and then recovered, it was found that the oxygen in the recovered cyclohexanone contained a significant amount of *O. Write a mechanism that explains this observation.
.Explain the most important nutritional role of carbohydrates and how they are created. Identify the basic structures of the major carbohydrates: monosaccharides, disaccharides, polysaccharides (e.g., starches), and fiber.
which of the following statements about mixed bonding is true? mixed bonding cannot occur in compounds that contain metals mixed bonding only occurs in organic molecules mixed bonding can result in materials with unique mechanical and electrical properties
An equilibrium is established for the reaction 2 CO(g) + MoO₂(s) ⇌ 2 CO₂(g) + Mo(s). Kp = 0.0111 and Q = 0.0245. Which way does the reaction need to shift to reach equilibrium? A forward B reverse C no shift is necessary, it is already at equilibrium.
2 Points) As an introduction to his class, Severus Snape teaches the first years at Hogwarts about hydrates. He begins with equations representing various dehydrations. Which of the following equations properly represents the dehydration of MgCO3·5H2O?
Casein does -----. Question 8 options: form the thick curd on top of milk (age gelation) by acid hydrolysis contain milk fat globule membrane make up less than 20 % of the total milk protein in a milk show good stability against heat denaturation
classify each characteristic as pertaining to atoms , elements , or both: 1.contain protons 2.the smallest amount of matter 3. a form of matter 4. defined by the number of protons they contain 5. substance composed of a single type of atom
The compound FeBr3 is an ionic compound where Fe (iron) has a positive charge. Using your understanding of ionic compounds, what is the correct positive charge for Fe (iron) Group of answer choices -3 cation -1 cation +1 cation. +3 cation. +8 cation
describe sodium borohydride. what are its properties? is it natural or made in a factory? describe sodium borohydride in relation to sodium hydride and lithium aluminum hydride. what are some similarities and differences
Small amounts of sugar solutions can be used as a minor analgesic for infants when given orally prior to mildly painful procedures, such as a heel prick for blood tests. How many grams of sucrose would you need to prepare 100 mL of a 24% sucrose solution?
Which of the species of the followinf pairs would you expect to have a larger, more positive, enthalpy of hydration, corresponting ti a less favored hydration A. Li+ or Na+ B. Rb+ or K+ C. Li+ or Cs+ D. Li+ or Be2+
One isotope of a metallic element has mass number 39 and has 20 neutrons in the nucleus. It forms an atomic ion having 18 electrons. Enter the symbol for this ion (give the symbol for the nucleus and give the ionic charge as a right superscript).
When using a separatory funnel containing two immiscible solvents, it is important to identify which solvent will be the top layer and which solvent will be the bottom layer. Which factor determines which layer rests on top and which rest on the bottom?
4.39 which of the folllowing paird has the higher boiling point explaina) Pentane or 2-methylbutane (b) Heptane or pentane (c) Propane or 2-chloropropane (d) Butane or 1-propanol (e) Butane or CH3COCH3
What is true for the following reaction at equilibrium? HF(aq) ⇄ H+(aq) + F-(aq) K=6.3 × 10-4 A. There will mostly be reactants B. There will mostly be products C. There will be an equal amount of products and reactants
Chemical Kinetics How will you collect data for this experiment? in-person Experiment 1 Exact concentration of H2O2 stock solution (M) 1.025 Temperature of water bath (°C) 21.0 Experiment 1: Volume of O2 vs time for decomposition of H2O2
If desflurane were accidentally put into a sevoflurane vaporizer, would the patient receive more or less anesthetic than intended? Explain your answer. The patient would receive more anesthetic since desflurane has a much Blank vapor pressure.
What solvent is used to elute the DNA? How do you think this differs from the composition of the wash buffers? Comment on the intermolecular forces between DNA and the wash buffer vs. DNA and the elution solvent.
Consider this overall reaction, which is experimentally observed to be second order in AB and zero order in C: AB + C ¡ A + BC Is the following mechanism valid for this reaction? AB + AB k ¡ 1 AB2 + A Slow AB2 + C k ¡ 2 AB + BC Fast
As the eluent moves the mixture through the column, it is collected in separate containers, known as fractions, at the bottom of the column. Why is it important that the eluent is collected in separate fractions rather than all in the same flask?
Decide if each item describes either covalent, ionic or hydrogen bonding. Note: you may use some terms more than once An atom of hydrogen has on eelectron in its first shell. one more electron is needed to fill this shell. In a molecule of H2,
Suppose that the half-life of steroids taken by an athlete is 35 days. Assuming that the steroids biodegrade by a first-order process, how long (in days) would it take for 164 of the initial dose to remain in the athlete's body?
When dicarboxylic acids (compounds with two –COOH groups in their structures) melt, they frequently decompose to produce 2 moles of CO2 gas for every 1 mole of dicarboxylic acid melted: $$HOOC(CH2)nCOOH(s)H(CH2)nH(l)+2CO2(l)
Indicate the reagents that would be used to resolve the following, discuss the reactions involved and specify the physical method that would be the best to separate the diastereomers of 2,3-pentadienedioic acid.
Enzymes typically work in very particular conditions. Under what conditions should pepsin work best? Low temperatures and high pH High temperatures and high pH Basic and acidic environments High temperatures and low pH
An element has the electron configuration 1s22s22p4 . For reactions that involve electron transfer, this element will likely? Group of answer choices Gain 2 electrons Gain 6 electrons Lose 6 electrons Be non-reactive Lose 2 electrons
Given the atomic number and atomic mass of element, determine the number of protons, the number of electrons (When the atom has no net charge), the electron configuration, and whether the atom is reactive or inert.
in part A.3 The dispensing of the edta solution is discontinued when the color turns to purple. Because of this technique error, will the calculated molarity of the edta A solution be too high, too low, or unaffected? explain
Which of the following formulas is (are) INCORRECT? rate x part = total rate x total = part part divided by total = rate part divided by rate = total total divided by rate = part both a and e. both b and e. both c and d.
1. Balance the following oxidation reactions by adding the appropriate components (be sure to include the e-). a. FeS2 ↔ Fe(OH)3 b. 2Cr3+ ↔ Cr2O72- c. Fe3O4 ↔ Fe2O3 d. ZnS ↔ ZnO + S
Which of the following reactions will be the fastest? Assume that the collision factors for the reactions are equal. 20 ANSWERS OPTIONS A Ea = 100 kJ/mol B Ea = 70 kJ/mol C Ea = 50 kJ/mol D The three reactions will have the same rate.
Which of the following ionic compounds is incorrectly named ? Group of answer choices (NH4)2SO3, ammonium sulfite PbO2, lead(II) oxide Ca3(PO4)2, calcium phosphate Cu2S, copper(I) sulfide Fe2O3, iron(III) oxide
step 1: H2O2 + I- to H2O + IO- step 2: H2O2 + IO- to H2O + O2 + I-. write out the rate law for each fundamental step and determine the molecularity for each step. identify the catalyst and intermediate of the reactions
The following reaction is at equilibrium at one atmosphere, in a closed container. Which, if any, of the following actions will decrease the total amount of CO2 gas present at equilibrium? NaOH(s) + CO2(g) ⟷ NaHCO3(s)
Consider the following spectrum. The compound used to generate this spectrum might have which of the following molecular formulas? C_(7)H_(16) C_(7)H_(16)O C_(7)H_(14) C_(7)H_(12) either C_(7)H_(14) or C_(7)H_(12)
Compound 2 is a light gray solid made of overlapping hexagonal crystals. When heated gently it starts to soften and develop an unpleasant smell about 50°C . above room temperature. is it ionic, molecular or can't decide
A 0.0310 M solution of an organic acid has an [H+] of 5.50×10-4 M . Using the values above, calculate the pH of the solution. What is the percent ionization of the acid? Calculate the Ka value of the acid.
An irregular shape object has a mass of 32 oz. A graduated cylinder with and initial volume of 18.9 mL. After the object was dropped in the graduated cylinder, it had a volume of 75 mL. What is the density of object g/mL)?
What is the overall charge (+, 0, or –) for the following amino acids at a pH of 5.97? Glycine (pI = 5.97) Overall charge: +0– Cysteine (pI = 5.07) Overall charge: +0– Histidine (pI = 7.59) Overall charge: +0–
Which base will make ~100% enolate from a general ketone? (select all that apply) Group of answer choices No answer text provided. No answer text provided. NaOH NaH NaNH2 NaOCH3 (CH3)3COK LDA DMF H2O none of these
A student was provided an unknown carbohydrate and asked to classify the type of saccharide. Which one of the following tests should the student perform? Ninhydrin test Iodine test Potassium permanganate test Bromine test
Is 2-pyridone aromatic? No, aromatic hydrogens absorb at about 4.5 ppmYes, aromatic hydrogens absorb at about 4.5 ppmNo, aromatic hydrogens absorb at about 9.2 ppmYes, aromatic hydrogens absorb at about 7.2 ppm
Would the sign of ΔSΔS be + or −− for the following changes? Match the words in the left column to the appropriate blanks in the sentences on the right. ResetHelp negative positive When a stick of dynamite explodes, ΔSΔS is Blank
Which molecular formula is consistent with the following mass spectrum data? M+* at m/z= 108, relative height=61.5% (M+2)** at m/z= 110, relative height=61.3% • C-H12 Cl O C2H,Br O C2H5Br • none of these • CgH12
A proposed mechanism has the following steps: Step 1: Ag+(aq) + Ce4+(aq) ↔ Ag2+(aq) + Ce3+(aq) Step 2: Tl+(aq) + Ag2+(aq) → Tl2+(aq) + Ag+(aq) Step 3: Tl2+(aq) + Ce4+(aq) → Tl3+(aq) + Ce3+(aq) What is the catalyst?
Solve each of the conversions below. Do not include units in the answers to this problem. A. 326.75 K = __________ degC. B. -146.2 degC = __________ K. C. 1054.65 K = __________ degC. D. 73 degC = __________ K
When added to uranyl solutions, magnesia MgO can precipitate uranium as a hydrated uranium trioxide UO3 · xH2 O. Write a balanced equation for this reaction. (Hint: MgO is converted to Mg2+ .)
The boiling point of cycloheptane is 118.5°C. Its constitutional isomer, 1,1-dimethylcyclopentane, has a boiling point of only 87.5°C. Explain the difference in the boiling points of these two C7H14 compounds.
How many years would it take for 4 grams of Carbon-14 to decay to 0.25 grams? (Recall: C-14 has a half-life of 5730 years). Question 18 options: 17 190 years 22 920 years none of the choices 5730 years 4 years
Solvents with very low boiling points, such as diethyl ether, can create pressure inside the separatory funnel as a result of shaking. The funnel should be immediately vented after shaking/mixing. True False Clear selection
Consider the rate law rate=k[A]^n [B]^m When the concentration of reactant A increases by a factor of 3.0 the initial rate of reaction increases by a factor of 1.0. What is the order of reaction for reactant A?
Which of the following coordination compounds will form a precipitate when treated with an aqueous solution of AgNO3? Group of answer choices [Cr(NH3)3Cl3] [Cr(NH3)6]Cl3 Na3[Cr(CN)6] all of these Na3[CrCl6]
Which of the following will result from the addition of a catalyst to a reaction? I. increases the rate of the reaction II. decreases the activation energy III. increases the value of k (rate constant)
Write the equilibrium constant expressions for K and Kp for the following equilibrium reaction. 2ZnS(s) + 3O2(g) ⇔ 2ZnO(s) + 2SO2(g) (Enter K= answer and Kp=answer on the same line with a space between them)
match each term with it's definition. the position of an equilibrium always shifts in such a direction as to relieve a stress applied to the system. A molecule that donates a proton when it encounters a proton acceptor.
Which of the following types of probe detection develops color on the blot itself and thus only allows one exposure to be obtained? Group of answer choices chromogenic chemifluorescent radioactive chemiluminescent
Hydrogen peroxide decomposes spontaneously to yield water and oxygen gas according to the reaction equation 2H2O2 (aq) --> 2H2O(l) + O2 (g) The activation energy for this reaction is 75 kJ mol^-1. The enzyme catalase
Consider the following four formulas: SO3SO3, B2H6B2H6, COCO, C4H4O2C4H4O2. Which of these formulas could be only an empirical formula, only a molecular formula, either a molecular or an empirical formula?
What type(s) of intermolecular forces are present between sodium chloride and ammonia? Question 3Select one or more: A. ion-dipole B. dispersion C. dipole-dipole D. ion-induced dipole E. dipole-induced dipole
Identify and explain each equivalence point, describing when and why phosphate species gain or lose protons. Discuss the buffering capabilities of the system at each pKa.
If your initial mixture had contained two compounds containing a carbonic acid and one containing an amine, would you expect to be able to separate the three compounds using this form of extraction?
The following step of radical halogenation of alkanes is characterized by the formation of alkyl radicals by the removal of hydrogen atoms. As a consequence, hydrohalic acids like HCl and HBr are also formed.
Measure 30mL of 1M CuSO4 in the 50mL graduated cylinder. Calculate the stoichiometric amount of aluminum foil needed to completely react to your CuSO4. Please use dimensional anaylsis to show work.
chlorine can be prepared in the laboratory by the reaction of maganese dioxide with hydrochloric acid HCl(aq) as described by the chemical equation MnO2(s) + 4 HCl(aq) - MnCl2(aq) + 2H2O(l) + Cl2(g)
1) What are some examples of colloids you would find in nature or your body? 2) What are their roles? 3) What are some examples of manmade colloids? Gel 4) How do they compare to naturally occurring colloids?
Aqueous solutions of acetic acid and barium hydroxide can neutralize each other to produce a compound that is soluble in water. Identify the chemical formulas of the anion and cation found in this compound.
Which of the following is a COMBINATION reaction? 2 NaCl(aq) + CaO(aq) → Na2O(aq) + CaCl2(aq) 2 NaClO3(s) → 2 NaCl(s) + 3 O2(g) 4 NaCl(s) + O2(g) → 2 Na2O(s) + 2 Cl2(g) 2 NaCl(s) + 3 O2(g) → 2 NaClO3(s)
Complete and balance the following equation for the reaction of Bi (bismuth) with excess Br2. Assume that Bi adopts its most common oxidation state. Include the physical states of reactants and products.
In part B.1. a student forgot to polish the magnesium metal which had evidence of rust on it. As a result of this error the reported magnesium to oxygen ratio will be ___________. too high unaffected too low
Which of the following solutions is the most basic? (i) 0.0025 M NaOH (ii) H2O (iii) 0.0025 M HI (iv) 0.005 M Ca(OH)2 (v) 0.005 M KOH Group of answer choices (i) (iii) (ii) (iv) (v)
Which of the following is paramagnetic? Group of answer choices [Mn(CN)6]4– (strong field) [Co(NH3)6]3+ (strong field) [Zn(H2O)6]2+ [Fe(CN)6]4– (strong field) [Cu(en)3]+
Explain how changing the reaction temperature effected the equilibrium of the cobalt (II) complex system. In which direction did the equilibrium shift when you decreased the reaction temperature?
drawn the amino acids arginine, lysine, aspartate, and glutamate at pH 1, 7, and 13, and state the charge of each amino acid at each pH. This means you will draw 12 structures.
Consider an equation s = 2.15t2 + 0.1421t + 1.260. Find the value of s rounded to the proper number of significant digits, if t = 3.7. Instruction: enter your response rounded to two significant digits. s =
which of the following is a true statement: metallic elements donate electrons while non-metalllic elements receive elecrons, metallic elements receive electrons while non-metallic elements donate electrons
If you initial mixture had contained two compounds containing carbon silk acids, and one containing in a mean, would you expect to be able to separate the three compounds using this form extraction?
Examine the biochemical reaction below: CH3CH2OH + NAD+ ↔ CH3CHO + NADH + H+ Which of the following products results from an oxidation of the substrate in the above reaction? EtOHNAD+NADHAcetaldehyde
A student sets up the following equation to convert a measurement. (The ? stands for a number the student is going to calculate.) Fill in the missing part of this equation. ⋅×−6.9103Ncm=?Nmm
Which is not the correct chemical formula for the compound named? Group of answer choices sodium carbonate, Na2CO3 phosphoric acid, H3PO4 nitric acid, HNO3 copper(II) nitrate, CuNO2 iron(III) oxide, Fe2O3
What is the expression for the rate law for the racemization process? Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a Your answer b c d
Based on their intermolecular forces, polarity and other physical characteristics, rank the solvents from highest to lowest ΔHvap: 1-butanol , 2-butanol , Cyclohexane , Ethyl acetate
Osmolality refers to milliosmoles of ions and molecules per _____ Group of answer choices kilogram of solvent (mOsm/kg) liter of solvent (mOsm/L) kilogram of solution (mOsm/kg) liter of solution (mOsm/L)
4. (5 pts) Will the linoleic acid in the soybean oil that you may consume be converted to glucose with a net yield in your liver? _________ Defend you answer by showing pertinent reactins. Yes or No
Two molecules, one linear and one non‐linear, that have the same number of atoms (N), will have the same number of normal modes.
For any pair of enantiomers, one enantiomer is dextrorotatory, and the other is levorotatory. For each member, the value of the specific rotation is exactly the same, but the sign is the opposite.
The linear equation also contains the value of k the pseudo-order rate constant for part 1 including units. Replace the units of absorbance with the concentration of the bromophenol blue
The addition of an alcohol to an acid chloride is an example of alcoholysis (alcohol addition with bond breakage). Consider the alcoholysis reaction below and answer the questions that follow.
In polar aprotic solvent, F- is a [ Select ] ["better", "worse"] nucleophile than I-. In polar protic solvent, F- is a [ Select ] ["worse", "better"] nucleophile than I-.
1) Based on your experience of the solubility of aniline in neutral water vs. in acidic hydrochloric acid, explain why most amine drugs are formulated as an acid salt instead of an amine?
Which of the following is true? i. The pH of a neutral solution is always 7.0. ii. For a neutral solution [H⁺] = [OH⁻]. Question 7 options: 1) i only 2) ii only 3) both i and ii 4) neither i or ii
A 25.00 mL solution of 0.08530 M NaI is titrated with 0.05030 M AgNO3. Given the 𝐾sp of AgI is 8.3×10^−17. When 24 mL of AgNO3 is added, calculate pAg+.
At pH 4.6, casein is (has) ______________________________. Question 29 options: net negative charge net positive charge maximum Interaction between two protein molecules maximum solubility
Define halogenation of an alkene. • It is the addition of HCl to the alkene. It is the addition of Cl to the alkene. It is the addition of H2O to the alkene. It is the addition of H2 to the alkene.
27. Double bonds can also act like Lewis bases, sharing their electrons with Lewis acids. Use curved arrows to show how each double bond below will react with HCl and draw the resulting
Molecules with NO plane of symmetry are chiral. Identify which of the following molecules are chiral. A Compound 1 B Compounds 1 and 2 C Compound 2 D Compounds 2 and 4 E Compound 4
In each case tell which SN2 reaction will proceed faster. 1. The displacement by I- on (a) CH3Cl or (b) CH3OTos. ab 2. The displacement on 1-iodopropane of (a) CH3O- or (b) CH3CO2-
The ΔG of the following reaction is –2.8 kcal/mol: acetyl phosphate + ADP ↔ acetate + ATPIs ADP greater than, lesser than, or equal to acetate in its affinity for phosphate? (4 marks)
Enter an abbreviated electron configuration for manganese: Express your answer in complete form, in order of increasing energy. For example, [He]2s22p2 would be entered as [He]2s^22p^2.
To convert mass of an atom in grams to moles you must divide by? Select the correct answer below: Planck's constant The number of electrons in the atom The molar mass Avogadro’s number
200 mg = __________ g 1.5 g = ____________ mg 15 L = ____________mL 2 tsp = ___________ mL ½ oz = __________ Tbs 2 Tbs = __________mL 2500 mL = _______ L
Match the electron structure below with the element type it represents.1s22s22p63s23p64s1 Group of answer choices Halogen Alkaline earth metal Alkali metal Inert gas Transition metal
What is the sum of these contributions? Report your answer to two decimal places. Mass contribution of 24Mg = 18.946 amu Mass contribution of 25Mg = 2.499 amu Mass contribution of 26Mg = 2.861 amu
Write the equilibrium constant expression Kia for the dissociation of acetic acid and the quilibrium constant expression for the dissociation of sodium acetate in
Describe all the steps of the radical halogenation mechanism Propane (CH3CH2CH3) with molecular chlorine (Cl2) (propose possible racemic mixture) (p. 255)
Which of the following carboxylic acid derivatives could be used in this forward reaction? X = Br X = Cl X = SCH3 X = OCH3 X = OH -OH is stronger base than the amide Question 6
During an extraction, if you become uncertain about which layer is the organic layer (and you don’t know the exact density of the solvents), what would you do to determine it experimentally
The signal at 1740 cm-1 in the IR spectrum of methyl 3-nitrobenzoate is due to what functional group? Question 1 options: the aromatic ring the ester group the methyl group the nitro group
Complete the following sentence: Osmosis is the passage of __________molecules from a _________ concentrated solution to a ___________concentrated solution through a _____________________
When some substances are dissolved in water, they undergo either a physical or a chemical change that yields ions in solution. These substances constitute an important class of compounds called
Suppose a 40. L reaction vessel is filled with 1.4 mol of NO and 1.4 mol of CO2. What can you say about the composition of the mixture in the vessel at equilibrium?
For each pound of _____ that enters surface water ________ pounds of algae can be the result. Question 27 options: K 1000 H 100 No2- 10 P 1000
What is the ground-state electronic configuration of a chlorine anion (Cl–)? Select one: A. 1s2, 2s2, 2p6, 3s2, 3p4 B. 1s2, 2s2, 2p6 C. 1s2, 2s2, 2p6, 3s2, 3p6 D. 1s2, 2s2, 2p6, 3s2, 3p5
Draw the structures of the six bromoalkenes with the molecular formula C5H9Br that have a branched carbon chain, and that show neither E,Z isomerism nor chirality.
Given that N2H4 + 2H2O2 yields N2 + 4(H20) and you have 6 mol of N2H4 and 4.5 mol of H2O2, why is one of the byproducts N2 in grams 2.25 times its molar weight ?
What is the freezing point of water made by dissolving 17.63 g of magnesium chloride in 92.40 g of water? The freezing-point depression constant of water is 1.86 oC/m.
enzymnes use several types of catalytic mechanisms. Classify each description as characteristic of acid-base catalysis, covalent catalysis,metal ion catalysis, or all three m echanims
Explain why the addition of solid calcium chloride resulted in an equilibrium shift toward the left, while the addition of solid calcium nitrate had no effect on the equilibrium.
Sucrose is hydrolyzed to give the following two monosaccharides. Which monosaccharide can be directly oxidized by Cu2+? Question 3 options: Both 1 and 2 Neither 1 only 2 only
Which of the following reactions describes the process of reducing silver to its visible metallic state without the aid of extraneous agents? argentaffin decidual argyrofilic luteinizing
Compare acidity of following metal ions when dissolved in water (same concentration and same counter anion): Ca2+, Rb+, Sr2+, Sc3+. Which of the following conclusion is wrong?
The reactant concentration in a first-order reaction was 7.40×10−2 M after 25.0 s and 6.80×10−3 M after 90.0 s . What is the rate constant for this reaction?
Some facts about the ethylene molecule:number of carbon-carbon single (C - C) bonds: 2 number of carbon-hydrogen single (C - H) bonds: 2 number of carbon-carbon double (C = C) bonds:
Which of the following ions does NOT have the same number of valence electrons as neon? Group of answer choices magnesium ion calcium ion sodium ion oxide ion fluoride ion
Alkyl Halides Methyl cyclobutene can react withHX (hydrogen halides) in an electrophilic addition reaction to form alkyl halides. Example: Reaction with HBr → Bromo-methyl cyclobutane.
2-57. Draw as many resonance structures as you can for the following species, adding appropriate formal charges to each: a. Nitromethane b. Ozone c. Diazomethne
From your predicted value of the van't Hoff factor, calculate the boiling point of a 1.60 m aqueous solution of barium nitrate, Ba(NO3)2. The Kb of water is 0.52°C/m.
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