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Chemistry 102
November 2024
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Chemistry 102
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November 11, 2024
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November 11 of 2024
1) what are the lambda max values for DNA and colorless proteins in solution? 2) what is the concentration of DNA in a sample if the OD at 260 nm is 0.43 au? 3) what us the relative purity of the sample in question 2 above if the OD at 280 nm is 0.29 au
5:22 LTE + (18\% \( \leftarrow \) Pulse OC1-Assignment 5-Chapter 5 1 of 25 - / 1 Draw a structural formula for an alkene with the indicated molecular formula that gives the compound shown as the major product. Note that more than one alkene may give the same compound as the major…
1) which type of spectrometry is used to measure alcohols in drug testing or in testing of biofuels? 2) which type of spectrometry is primarily used to measure chemical contamination of soil or ground water? 3) Urea concentration is an indicator of kidney failure. What type of spectrometry is…
This is chemical engineering but that option isn't available. Assistance appreciated.
Dinitrogen tetraoxide and nitrogen dioxide are two gases that exist in equilibrium at a range of temperatures. is a reddish brown gas while is colorless. At high temperature the red color is strong. At low temperature the gas has less color. If we represent the equilibrium as: We can…
Consider the following system at equilibrium where delta H=-18.8 kJ, and Kc=1.05x10^1, at 350 K: 2CH2Cl2(g)->CH4(g)+CCl4(g) If the temperature on the equilibrium system is suddenly increased: The value of Kc increases decreases remains the same The value of Qc is less than Kc is greater than…
Consider the following system at equilibrium where delta H=-87.9 kJ, and Kc=83.3, at 5.00x10^2 K: PCl3(g)+Cl2(g)->PCl5(g) If the temperature on the equilibrium system is suddenly decreased: The value of Kc increases decreases remains the same The value of Qc is less than Kc is greater than…
In an aqueous chloride solution cobalt(II) exists in equilibrium with the complex ion CoCl4 2-. Co2+ (aq) is pink and CoCl4 2- (aq) is blue. If we represent the equilibrium as: CoCl4 2-(aq)-> Co2+(aq) +4Cl-(aq) We can conclude that: In an aqueous chloride solution cobalt(II) exists in…
In an aqueous chloride solution cobalt(II) exists in equilibrium with the complex ion CoCl4 2-. Co2+ (aq) is pink and CoCl4 2- (aq) is blue. If we represent the equilibrium as: CoCl4 2-(aq)-> Co2+(aq) +4Cl-(aq) We can conclude that: In an aqueous chloride solution cobalt(II) exists in…
In an aqueous chloride solution cobalt(II) exists in equilibrium with the complex ion CoCl4 2-. Co2+ (aq) is pink and CoCl4 2- (aq) is blue. If we represent the equilibrium as: CoCl4 2-(aq)-> Co2+(aq) +4Cl-(aq) We can conclude that:
Consider the following system at equilibrium where delta H=-18.8 kJ , and Kc=10.5 , at 350 K: 2CH2Cl2(g)-> CH4(g)+CCl4(g) If the VOLUME on the equilibrium system is suddenly increased at constant temperature: The value of Kc increases decreases remains the same The value of Qc is greater than…
Consider the following system at equilibrium where delta H=-87.9 kJ and Kc=83.3 , at 500. K. PCl3(g)+Cl2(g)-> PCl5(g) If the VOLUME of the equilibrium system is suddenly decreased at constant temperature: The value of Kc increases decreases remains the same The value of Qc is greater than Kc…
initial condition new condition Fill in the blank with the CORRECT number. The rate at the initial condition is \( 0.02 \mathrm{~mol} /(\mathrm{L} \cdot \mathrm{s}) \). The rate is \( \square \) \( \mathrm{mol} /(\mathrm{L} \cdot \mathrm{s}) \) at the new condition, assuming the reaction is…
1. A compound with the molecular formula ( mathrm{C}_{5} mathrm{H}_{10} mathrm{O}_{2} ) has the following 1 H NMR spectrum. Proton NMR Determine the number of hydrogens (protons) giving rise to each peak [5] A. ( mathrm{A}=2, mathrm{~B}=3, mathrm{C}=2, mathrm{D}=3 ) B. ( mathrm{A}=5,…
Using spectrophotometry to Measure DNA concentration and Purity. 1) what is lambda max and why is it important? 2) what is lambda max for colorless proteins? 3) How is Bradford reagent used to detect a specific protein in solution?
Question 1 of 4 Question 1: Use the following reactions (i-iii) to calculate the standard heat of formation of \( \mathrm{C}_{3} \mathrm{H}_{8} \) (g). (i) \( \mathrm{C}_{3} \mathrm{H}_{8}(\mathrm{~g})+5 \mathrm{O}_{2}(\mathrm{~g}) \rightarrow 3 \mathrm{CO}_{2}(\mathrm{~g})+4 \mathrm{H}_{2}…
CH 22 OWL HW Set - Due No OWLv2 | Online teaching and N. cooh cooh oh oh oh ozn selec prod02-cnow-owl.cengagenow.com/ilrn/takeAssignment/takeCovalentActivity.do?locator=assignment-take New Chrome available CH 22 OWL HW Set - Due November 19 [References] Question 1 1 pt Question 2 1 pt Question…
This is chemical engineering but that option isn't available. Assistance appreciated.
This is chemical engineering but that option isn't available. Assistance appreciated.
Study the graph below. The enthalpy change for the formation of carbon dioxide and hydrogen gases from their constituent elements is -393.5 kJ . Drag and drop the options to correctly label the diagram.
Experiment 30 data and calculations
\( \qquad \) amperage gives better sensitivity. Lower Unrectified half-wave Higher Milli-
Most specifications require the \( \qquad \) method, which is more sensitive than the \( \qquad \) method. residual; continuous residual; discontinuous continuous; residual discontinuous; residual
A solution of iodine has an iodine titer of 11.43 mg. What is its As2O3 titer? What is the normality of the iodine solution?
A solution of iodine has an iodine titer of 11.43 mg. What is its As2O3 titer? What is the normality of the iodine solution? The answers are 4.45mg and 0.900N i just need to know how the solving is. Please apply the N X V = g / gmew rule
What sample weight of each of the following would be used so that 35ml of 0.1 N iodine would be consumed in the titration? Compare with the sample weights specified in the USP and NF assay procedures: (a) sodium thiosulfate, (b) stibophen, (c) sodium ascorbate. The answers are (a) 553.35 mg (b)…
A solution of iodine has an iodine titer of 11.43 mg. What is its As2O3 titer? What is the normality of the iodine solution? The answers are 4.45mg and 0.900N i just need to know how the solving is
What sample weight of each of the following would be used so that 35ml of 0.1 N iodine would be consumed in the titration? Compare with the sample weights specified in the USP and NF assay procedures: (a) sodium thiosulfate, (b) stibophen, (c) sodium ascorbate.
A solution of iodine has an iodine titer of 11.43 mg. What is its As2O3 titer? What is the normality of the iodine solution?
How many total atoms are there in 0.350 mol of potassium bromite, \( \mathrm{KBrO}_{2} \) ? Feedback Sorry, that's inc \[ 0.350 \mathrm{~mol}=\frac{9.548 \times 10^{25}}{\text { Incorrect Answer }^{9.5}} \] \begin{tabular}{|c|} \hline factor betwee formula units. \\ \hline \end{tabular}
How many total atoms are there in 0.350 mol of potassium bromite, \( \mathrm{KBrO}_{2} \) ? Feedback Sorry, that's inc \[ 0.350 \mathrm{~mol}=\frac{9.548 \times 10^{25}}{\text { Incorrect Answer }^{9.5}} \] \begin{tabular}{|c|} \hline factor betwee formula units. \\ \hline \end{tabular}
69. Complete and balance the chemical equations for the precipitation reactions, between the following pairs of reactants, and write the net ionic equations: a. \( \mathrm{Pb}\left(\mathrm{NO}_{3}\right)_{2}(a q)+\mathrm{Na}_{2} \mathrm{SO}_{4}(a q) \rightarrow \) b. \( \mathrm{NiCl}_{2}(a…
8.69. Complete and Datance the chemical equations for the precipitation reactions, between the following pairs of reactants, and write the net ionic equations: a. \( \mathrm{Pb}\left(\mathrm{NO}_{3}\right)_{2}(\mathrm{aq})+\mathrm{Na}_{2} \mathrm{SO}_{4}(\mathrm{aq}) \rightarrow \) b. \(…
2 Fill in the Blank 0.5 points Consider a 0.00550 M weak acid solution with a percent ionization of 8.20\%. Round each answer to TWO places past the decimal in scientific notation and for pH . Part A: What is the concentration of \( \mathrm{H}^{+} \)(in M) at…
The furnace wall is covered with 3 layers: fire brick with a thickness of 8 in (k=0.95 Btu/h.ft.oF), insulating brick (k=0.4 Btu/h.ft.oF) and common brick (k=0.8 Btu/h.ft.oF). Fire brick entry temperature, T1= 1600oF, the maximum temperature of the insulating brick, T2= 1500oF and temperature…
5. Consider the following reaction at 298 K : \[ 2 \mathrm{H}_{2(\mathrm{~g})}+\mathrm{O}_{2(\mathrm{~g})} \rightarrow 2 \mathrm{H}_{2} \mathrm{O}_{(\mathrm{l})} \quad \Delta \mathrm{H}^{\circ}=-571.6 \mathrm{~kJ} / \mathrm{mol} \] Calculate the \( \Delta \mathrm{S}_{\text {sys }}, \Delta…
4. In the given reaction below, there is one species for which the standard entropy value is not listed in Thermodynamic Table handout given and posted on Canvas. Determine the \( S^{\circ} \) for that species. Hint: Set-up the equation and you will see which one is missing. (a) The \( \Delta…
1 Fill in the Blank 0.3 points Consider a \( 1 \mathrm{M} \mathrm{HNO}_{2}\left(K_{a}=4.5 \times 10^{-4}\right) \) solution. Part A: What is the concentration of \( \mathrm{H}^{+} \)(in M) at equilibrium? Round your answer to THREE places past the decimal. \[ \left[\mathrm{H}^{+}\right]=\text…
4. In the given reaction below, there is one species for which the standard entropy value is not listed in Thermodynamic Table handout given and posted on Canvas. Determine the \( S^{\circ} \) for that species. Hint: Set-up the equation and you will see which one is missing. (a) The \( \Delta…
For each of the following compounds, decide whether the compound's solubility in aqueous solution changes with pH. If the solubility does change, pick the pH at which you'd expect the highest solubility. You'll find \( K_{s p} \) data in the ALEKS Data tab. \begin{tabular}{|c|c|c|c|c|} \hline…
For each of the following compounds, decide whether the compound's solubility in aqueous solution changes with pH. If the solubility does change, pick the pH at which you'd expect the highest solubility. You'll find \( K_{s p} \) data in the ALEKS Data tab. \begin{tabular}{|c|c|c|c|c|} \hline…
6. As an approximation, we can assume that proteins exist either in the native (or physiologically functioning) state and the denatured state [ native \( \leftrightarrow \) denatured ]. The standard molar enthalpy and entropy of the denaturation of a certain protein are \( 512 \mathrm{~kJ} /…
Part E: What is the pH of a \( 7.0 \times 10^{-3} \mathrm{M} \) aqueous solution of \( \mathrm{Ca}(\mathrm{OH})_{2} \) at \( 25^{\circ} \mathrm{C} \) ? Round your answer to TWO places past the decimal. \[ \mathrm{pH}= \] type your answer...
Part D: If the pOH of a \( \mathrm{Ba}(\mathrm{OH})_{2} \) solution is 1.88 at \( 25^{\circ} \mathrm{C} \), what is the concentration (in M) of barium hydroxide? Round your answer to FOUR places past the decimal. \[ \left[\mathrm{Ba}(\mathrm{OH})_{2}\right]=\text { type your answer... }…
Part C: If the pOH of a KOH solution is 1.88 at \( 25^{\circ} \mathrm{C} \), what is the hydroxide concentration (in M )? Round your answer to FOUR places past the decimal. \( \left[\mathrm{OH}^{-}\right]= \) \( \square \) type your answer... M
Part B: What is the pH of a 0.162 M KOH solution? Round your answer to TWO places past the decimal. \( \mathrm{pH}= \) type your answer... \( \square \)
The solubility of \( \mathrm{Mg}(\mathrm{OH})_{2} \) in water at \( 25^{\circ} \mathrm{C} \) is measured to be \( 0.0096 \frac{\mathrm{~g}}{\mathrm{~L}} \). Use this information to calculate \( K_{s p} \) for \( \mathrm{Mg}(\mathrm{OH})_{2} \). Round your answer to 2 significant digits.
A certain reaction has the enthalpy of the reaction =-19.5 kJ/mol and the entropy of the reaction is 42.7 kJ/mol at 25°C. Which of the following statements is/are TRUE assuming the H and S are temperature independent ? a. The reaction is non-spontaneous at the given temperature b. The…
12 Fill in the Blank 3 points Consider the following strong acid or strong base solutions. Part A: What is the pH of a \( 0.054 \mathrm{M} \mathrm{HNO}_{3} \) solution? Round your answer to TWO places past the decimal. \[ \mathrm{pH}=\text { type your answer... } \]
36. What happens when you add NaOH to a solution of acetic acid ( \( \mathbf{C H}, \mathrm{COOH}) \) ? A) The pH of the solution increases and the acid dissociation decreases B) The pH of the solution increases and the acid dissociation increases C) The pH of the solution decreases and the acid…
Use the provided component (in bold blue front) to complete the remaining values in the table
Which of the following steps in solution formation is exothermic? a. overcoming the solute-solute intermolecular forces b. overcoming the solvent-solute intermolecular forces c. overcoming the solvent-solvent intermolecular forces d. establishing the solute-solvent intermolecular forces
Which of the following ions will contribute most to elevating the boiling point of Hâ‚‚O? a. Na+ b. K+ c. Ca2+ d. All will contribute equally
What is the osmotic pressure, in atm, of a 0.197 M solution of MgCl₂ at 37.0 °C? (assume complete dissociation).
When writing the chemical formula for an ionic compound, which element should be written first? The cation and anion switch each time a formula is written. Sometimes the cation and sometimes the anion. The cation goes first. The anion goes first.
11 Fill in the Blank 1.6 points Use the provided component (in bold blue font) to complete the remaining values in the table. Hint: When using pH or pOH to solve for concentration, keep the pH or pOH value at two places past the decimal. Once you solve for concentration, you can enter your…
10 Fill in the Blank 0.3 points At an elevated temperature, the \( K_{w} \) of pure water has a value of 2.5 x \( 10^{-13} \). Part A: What is the pH of pure water at this temperature? Round your answer to ONE place past the decimal. \[ \mathrm{pH}=\text { type your answer... } \] Part B:…
What is the osmotic pressure, in atm, of a solution made from 22.3 g of methanol (MM = 32.04 g/mol) that was added to water to make 781 mL of solution at 25.0 °C?
What is the molarity of a solution of a polypeptide which has an osmotic pressure of 0.223 atm at 37.0 °C?
What mass in grams of NaCl would need to be added to 2301 g of water to increase the boiling temperature of the solution by 1.500 °C? (Kb for water is 0.5100 °C/m)
MgCl₂ has a van't Hoff factor of 2.70. What would be the boiling point (in °C) of an aqueous solution containing 4.30 mol of MgCl₂ in 1.00 kg of water? (Kb for water is 0.512 °C/m. The boiling point for water is 100.0˚C.)
Which of the following aqueous solutions is predicted to have the highest boiling point? a. 1.0 m NaNO3 b. 1.0 m HF c. 1.0 m C6H12O6 d. 1.0 m CaCl2
This is chemical engineering but that option isn't available. Assistance appreciated.
8 Fill in the Blank 1 point Predict the side of the reaction favored at equilibrium for each aqueous acid/base reaction. Part A: Reaction 1 \begin{tabular}{|c|c|c|c|c|} \hline HI & \( +\mathrm{F}^{-} \) & \( \rightleftharpoons \) & HF & \( +\mathrm{I}^{-} \) \\ \hline strong \( \epsilon \vee…
Part B: Consider the acid/base equilibrium below given the \( K_{c}=1 \times 10^{-4} \). \[ \mathrm{H}_{2} \mathrm{X}+\mathrm{Z}^{-} \rightleftharpoons \mathrm{HX}^{-}+\mathrm{HZ} \] This reaction is choose your answer... at equilibrium. Strongest acid: Answer Strongest base: Answer
The freezing point of pure benzene (C₆H₆) is 5.49 °C. The freezing point of a solution made using toluene (C₇H₈) in benzene is determined to be -13.0 °C. What is the molality of the toluene? (Kf benzene = 5.12 °C/m)
7 0.3 points Consider the equilibrium position of an acid/base reaction. Part A: Complete the following statements to summarize what is true about the position of equilibrium in an acid/base reaction. In an acid/base equilibrium, the position of equilibrium favors the choose your answer...…
FeCl₃ has a van't Hoff factor of 3.400. What is the freezing point (in °C) of an aqueous solution made with 0.9600 m FeCl₃? (Kf for water is 1.860 °C/m)
Calculate the \( \Delta \mathrm{S}^{\circ} \) (in \( \mathrm{J} / \mathrm{mol} \mathrm{K} \) ) of the following reaction using the given values: \( \mathrm{S}^{\circ}[\mathrm{NO}(\mathrm{g})]= \) \( 210.8 \mathrm{~J} / \mathrm{mol} \mathrm{K} ;…
Calculate the \( \Delta \mathrm{S}^{\circ} \) (in \( \mathrm{J} / \mathrm{mol} \mathrm{K} \) ) of the following reaction using the given values: \( \mathrm{S}^{\circ}\left[\mathrm{NH}_{3}(\mathrm{~g})\right]= \) 192.5 J/mol K; \( \mathrm{S}^{\circ}\left[\mathrm{O}_{2}(\mathrm{~g})\right]=205.1…
Calculate the \( \Delta \mathrm{S}^{\circ} \) (in \( \mathrm{J} / \mathrm{mol} \mathrm{K} \) ) of the following reaction using the given values: \( \mathrm{S}^{\circ}\left[\mathrm{NH}_{3}(\mathrm{~g})\right]= \) 192.5 J/mol K; \( \mathrm{S}^{\circ}\left[\mathrm{O}_{2}(\mathrm{~g})\right]=205.1…
Which one of the following aqueous solutions would have the highest freezing point? a. 1.0 m NaNO3 b. 2.0 m CH3OH c. 1.0 m C6H12O6 d. 1.0m CaCl2
Which of the following solutes will lower the freezing point the most in 1 L Hâ‚‚O? a. 1 mol Nal b. 1 mol Kl c. 1 mol Mgl_2 d. All would lower the freezing point equally
6 Ordering 0.4 points Rank the following acids' conjugate bases in terms of their strength as a base. \begin{tabular}{|c|c|} \hline Acid & \( \boldsymbol{K}_{\boldsymbol{a}} \) \\ \hline \( \mathrm{CH}_{3} \mathrm{COOH} \) & \( 1.8 \times 10^{-5} \) \\ \hline \( \mathrm{HNO}_{2} \) & \( 4.5…
This is chemical engineering but that option isn't available. Assistance appreciated.
(a) (b) (c) (d) Rank the images in terms of the relative strength of HX as an acid from most acidic at the top to least acidic (neutral) at the bottom. HX = Strongest Acid 1 (c) 2 (b) 3 (a) 4 (d) HX = Least Acidic / Neutral Compound
This is chemical engineering but that option isn't available. Assistance appreciated.
4 Categorization 1.4 points Identify the following as either acids or bases AND if these are strong or weak. Strong Acids Strong Bases \( \mathrm{H}_{2} \mathrm{SO}_{4} \) \( \mathrm{HNO}_{3} \) \( \mathrm{H}_{3} \mathrm{O}^{+} \) \( \mathrm{Ba}(\mathrm{OH})_{2} \) \( \mathrm{OH}^{-} \) Weak…
This is chemical engineering but that option isn't available. Assistance appreciated.
This is chemical engineering but that option isn't available. Assistance appreciated.
This is chemical engineering but that option isn't available. Assistance appreciated.
Part C: \[ \mathrm{CO}_{3}{ }^{2-}(a q) \quad+\quad \mathrm{H}_{2} \mathrm{O}(I) \] \( \mathrm{HCO}_{3}{ }^{-}(a q) \) \( + \) \( \mathrm{OH}^{-}(a q) \) acid base \( \rightleftharpoons \) conjugate base conjugate acid
Part B: \[ \begin{array}{llllll} \mathrm{H}_{2} \mathrm{PO}_{4}^{-}(a q) & +\quad \mathrm{NH}_{3}(a q) & \mathrm{HPO}_{4}{ }^{2-}(a q) & \mathrm{NH}_{4}^{+}(a q) \end{array} \] choose your answer... choose your answer... choose your answer... choose your answer...
3 Fill in the Blank 1.2 points Identify the Bronsted-Lowry conjugate acid-base pairs in each of the following reactions. Part A: \[ \mathrm{CH}_{3} \mathrm{COO}^{-}(\mathrm{aq}) \quad+ \] HCN (aq) \( \qquad \) \( \mathrm{CH}_{3} \mathrm{OOH} \) (aq) \( + \) \( \qquad \) \( \mathrm{CN}^{-}(a…
2 Fill in the Blank 0.2 points The nitrite anion is a common ligand in complex ion formation. A coordinate-covalent bond within a complex ion is often a Lewis acid/base interaction. Part A: Which species is the Lewis acid? choose your answer... Part B: Which species is the Lewis base? choose…
1 Multiple Choice 0.2 points When sodium fluoride is added to water, it dissolves and the resulting fluoride ions react with water according to the following reaction: \[ \mathrm{F}^{-}(a q)+\mathrm{H}_{2} \mathrm{O}(l) \rightleftharpoons \mathrm{HF}(a q)+\mathrm{OH}^{-}(a q) \] What is the…
1) what are the lambda max values for DNA and colorless proteins in solution? 2) what is the concentration of DNA in a sample if the OD at 260 nm is 0.43 au? 3) what us the relative purity of the sample in question 2 above if the OD at 280 nm is 0.29 au
1) which type of spectrometry is used to measure alcohols in drug testing or in testing of biofuels? 2) which type of spectrometry is primarily used to measure chemical contamination of soil or ground water? 3) Urea concentration is an indicator of kidney failure. What type of spectrometry is…
Using spectrophotometry to Measure DNA concentration and Purity. 1) what is lambda max and why is it important? 2) what is lambda max for colorless proteins? 3) How is Bradford reagent used to detect a specific protein in solution?
A solution of iodine has an iodine titer of 11.43 mg. What is its As2O3 titer? What is the normality of the iodine solution?
What sample weight of each of the following would be used so that 35ml of 0.1 N iodine would be consumed in the titration? Compare with the sample weights specified in the USP and NF assay procedures: (a) sodium thiosulfate, (b) stibophen, (c) sodium ascorbate.
The furnace wall is covered with 3 layers: fire brick with a thickness of 8 in (k=0.95 Btu/h.ft.oF), insulating brick (k=0.4 Btu/h.ft.oF) and common brick (k=0.8 Btu/h.ft.oF). Fire brick entry temperature, T1= 1600oF, the maximum temperature of the insulating brick, T2= 1500oF and temperature…
Which one of the following aqueous solutions would have the highest freezing point? a. 1.0 m NaNO3 b. 2.0 m CH3OH c. 1.0 m C6H12O6 d. 1.0m CaCl2