Chapter Questions
Which of the following is true about an individual atom?Explain.a. An individual atom should be considered to be a solid.b. An individual atom should be considered to be a liquid.c. An individual atom should be considered to be a gas.d. The state of the atom depends on which element it is.e. An individual atom cannot be considered to be a solid,liquid, or gas.
How would you go about finding the number of “chalk molecules” it takes to write your name on the board? Provide an explanation of all you would need to do and a sample calculation.
These questions concern the work of J. J. Thomson.a. From Thomson’s work, which particles do you think he would feel are most important for the formation of compounds (chemical changes) and why?b. Of the remaining two subatomic particles, which do you place second in importance for forming compounds and why?c. Propose three models that explain Thomson’s findings and evaluate them. To be complete you should include Thomson’s findings.
Heat is applied to an ice cube in a closed container until only steam is present. Draw a representation of this process, assuming you can see it at an extremely high level of magnification. What happens to the size of the molecules? What happens to the total mass of the sample?
You have a chemical in a sealed glass container filled with air. The setup is sitting on a balance as shown below. The chemical is ignited by means of a magnifying glass focusing sunlight on the reactant. After the chemical has completely burned, which of the following is true? Explain your answer.a. The balance will read less than 250.0 g.b. The balance will read 250.0 g.c. The balance will read greater than 250.0 g.d. Cannot be determined without knowing the identity of the chemical.
The formula of water is$\mathrm{H}_{2} \mathrm{O}$. Which of the following is indicated by this formula? Explain your answer.a. The mass of hydrogen is twice that of oxygen in each molecule.b. There are two hydrogen atoms and one oxygen atom per water molecule.c. The mass of oxygen is twice that of hydrogen in each molecule.d. There are two oxygen atoms and one hydrogen atom per water molecule.
You may have noticed that when water boils, you can see bubbles that rise to the surface of the water. Which of the following is inside these bubbles? Explain.a. airb. hydrogen and oxygen gasc. oxygen gasd. water vapore. carbon dioxide gas
One of the best indications of a useful theory is that it raises more questions for further experimentation than it originally answered. Does this apply to Dalton’s atomic theory? Give examples.
Dalton assumed that all atoms of the same element were identical in all their properties. Explain why this assumption is not valid.
Why is the term “sodium chloride molecule” incorrect whereas the term “carbon dioxide molecule” is correct?
Evaluate each of the following as an acceptable name for water:a. dihydrogen oxideb. hydroxide hydridec. hydrogen hydroxided. oxygen dihydride
Why do we call $\mathrm{Ba}\left(\mathrm{NO}_{3}\right)_{2}$ barium nitrate, but we call $\mathrm{Fe}\left(\mathrm{NO}_{3}\right)_{2}$ iron(II) nitrate?
Why is calcium dichloride not the correct systematic name for $\mathrm{CaCl}_{2} ?$
The common name for $\mathrm{NH}_{3}$ is ammonia. What would be the systematic name for $\mathrm{NH}_{3} ?$ Support your answer.
Which (if any) of the following can be determined by knowing the number of protons in a neutral element? Explain your answer.a. the number of neutrons in the neutral elementb. the number of electrons in the neutral elementc. the name of the element
Which of the following explain how an ion is formed? Explain your answer.a. adding or subtracting protons to/from an atomb. adding or subtracting neutrons to/from an atomc. adding or subtracting electrons to/from an atom
What refinements had to be made in Dalton’s atomic theory to account for Gay-Lussac’s results on the combining volumes of gases?
When hydrogen is burned in oxygen to form water, the composition of water formed does not depend on the amount of oxygen reacted. Interpret this in terms of the law of definite proportion.
The two most reactive families of elements are the halogens and the alkali metals. How do they differ in their reactivities?
Explain the law of conservation of mass, the law of definite proportion, and the law of multiple proportions.
Section 2.3 describes the postulates of Dalton’s atomic theory. With some modifications, these postulates hold up very well regarding how we view elements, compounds, and chemical reactions today. Answer the following questions concerning Dalton’s atomic theory and the modifications made today.a. The atom can be broken down into smaller parts. What are the smaller parts?b. How are atoms of hydrogen identical to each other, and how can they be different from each other?c. How are atoms of hydrogen different from atoms of helium? How can H atoms be similar to He atoms?d. How is water different from hydrogen peroxide $\left(\mathrm{H}_{2} \mathrm{O}_{2}\right)$even though both compounds are composed of only hydrogen and oxygen?e. What happens in a chemical reaction, and why is mass conserved in a chemical reaction?
The contributions of J. J. Thomson and Ernest Rutherford led the way to today’s understanding of the structure of the atom. What were their contributions?
What is the modern view of the structure of the atom?
The number of protons in an atom determines the identity of the atom. What does the number and arrangement of the electrons in an atom determine? What does the number of neutrons in an atom determine?
If the volume of a proton were similar to the volume of an electron, how will the densities of these two particles compare to each other?
For lighter, stable isotopes, the ratio of the mass number to the atomic number is close to a certain value. What is the value? What happens to the value of the mass number to atomic number ratio as stable isotopes become heavier?
List some characteristic properties that distinguish the metallic elements from the nonmetallic elements
Consider the elements of Group 4A (the “carbon family”): C, Si, Ge, Sn, and Pb. What is the trend in metallic character as one goes down this group? What is the trend in metallic character going from left to right across a period in the periodic table?
Chlorine has two natural isotopes: $_{17}^{37} \mathrm{Cl}$ and 3517 $\mathrm{Cl}$ Hydrogen reacts with chlorine to form the compound HCl. Would a given amount of hydrogen react with different masses of the two chlorine isotopes? Does this conflict with the law of definite proportion? Why or why not?
Before an electrocardiogram (ECG) is recorded for a cardiac patient, the ECG leads are usually coated with a moist paste containing sodium chloride. Why is sodium chloride applied to the leads?
Distinguish between the following terms.a. molecule versus ionb. covalent bonding versus ionic bondingc. molecule versus compoundd. anion versus cation
Label the type of bonding for each of the following.
The vitamin niacin (nicotinic acid, $\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{NO}_{2} )$ can be isolated from a variety of natural sources such as liver, yeast, milk, and whole grain. It also can be synthesized from commercially available materials. From a nutritional point of view, which source of nicotinic acid is best for use in a multivitamin tablet? Why?
Which of the following statements is(are) true? For the false statements, correct them.a. Most of the known elements are metals.b. Element 118 should be a nonmetal.c. Hydrogen has mostly metallic properties.d. A family of elements is also known as a period of elementse. When an alkaline earth metal, A, reacts with a halogen, X, the formula of the covalent compound formed should be $\mathrm{A}_{2} \mathrm{X}$ .
Each of the following compounds has three possible names listed for it. For each compound, what is the correct name and why aren’t the other names used?a. $\mathrm{N}_{2} \mathrm{O} :$ nitrogen oxide, nitrogen(1) oxide, dinitrogen monoxideb. $\mathrm{Cu}_{2} \mathrm{O}$ : copper oxide, copper(1) oxide, dicopper monoxidec. $\mathrm{Li}_{2} \mathrm{O}$ : lithium oxide, lithium(1) oxide, dilithium monoxide
When mixtures of gaseous $\mathrm{H}_{2}$ and gaseous $\mathrm{Cl}_{2}$ react, a product forms that has the same properties regardless of the relative amounts of $\mathrm{H}_{2}$ and $\mathrm{Cl}_{2}$ used.a. How is this result interpreted in terms of the law of definite proportion?b. When a volume of $\mathrm{H}_{2}$ reacts with an equal volume of $\mathrm{Cl}_{2}$ at the same temperature and pressure, what volume of product having the formula HCl is formed?
Observations of the reaction between nitrogen gas and hydrogen gas show us that 1 volume of nitrogen reacts with 3 volumes of hydrogen to make 2 volumes of gaseous product, as shown below:
Determine the formula of the product and justify your answer.
A sample of chloroform is found to contain 12.0 g of carbon, 106.4 g of chlorine, and 1.01 g of hydrogen. If a second sample of chloroform is found to contain 30.0 g of carbon, what is the total mass of chloroform in the second sample?
A sample of $\mathrm{H}_{2} \mathrm{SO}_{4}$ contains 2.02 $\mathrm{g}$ of hydrogen, 32.07 $\mathrm{g}$ of sulfur, and 64.00 $\mathrm{g}$ of oxygen. How many grams of sulfur and grams of oxygen are present in a second sample of $\mathrm{H}_{2} \mathrm{SO}_{4}$ containing 7.27 $\mathrm{g}$ of hydrogen?
Consider 80.0-g samples of two different compounds consisting of only carbon and oxygen. One of the compounds consists of 21.8 g of carbon, and the other has 34.3 g of carbon. Determine the ratio in whole numbers of the masses of carbon that combine with 1.00 g of oxygen between the two compounds.
Several compounds containing sulfur and fluorine are known. Three of them have the following compositions:i. 1.188 $\mathrm{g}$ of $\mathrm{F}$ for every 1.000 $\mathrm{g}$ of $\mathrm{S}$ii. 2.375 $\mathrm{g}$ of $\mathrm{F}$ for every 1.000 $\mathrm{g}$ of $\mathrm{S}$iii. 3.563 $\mathrm{g}$ of $\mathrm{F}$ for every 1.000 $\mathrm{g}$ of $\mathrm{S}$How do these data illustrate the law of multiple proportions?
The three most stable oxides of carbon are carbon monoxide $(\mathrm{CO}),$ carbon dioxide $\left(\mathrm{CO}_{2}\right),$ and carbon suboxide $\left(\mathrm{C}_{3} \mathrm{O}_{2}\right) .$ The molecules can be represented as... Explain how these molecules illustrate the law of multiple proportions.
Two elements, R and Q, combine to form two binary compounds. In the first compound, 14.0 g of R combines with 3.00 g of Q. In the second compound, 7.00 g of R combines with 4.50 g of Q. Show that these data are in accord with the law of multiple proportions. If the formula of the second compound is RQ, what is the formula of the first compound?
In Section 1.1 of the text, the concept of a chemical reaction was introduced with the example of the decomposition of water, represented as follows:Use ideas from Dalton’s atomic theory to explain how the above representation illustrates the law of conservation of mass.
In a combustion reaction, 46.0 g of ethanol reacts with 96.0 g of oxygen to produce water and carbon dioxide. If 54.0 g of water is produced, what mass of carbon dioxide is produced?
Early tables of atomic weights (masses) were generated by measuring the mass of a substance that reacts with 1.00 g of oxygen. Given the following data and taking the atomic mass of hydrogen as 1.00, generate a table of relative atomic masses for oxygen, sodium, and magnesium.How do your values compare with those in the periodic table?How do you account for any differences?
Indium oxide contains 4.784 $\mathrm{g}$ of indium for every 1.000 $\mathrm{g}$ of oxygen. In $1869,$ when Mendeleev first presented his version of the periodic table, he proposed the formula $\operatorname{In}_{2} \mathrm{O}_{3}$ for indium oxide. Before that time it was thought that the formula was InO. What values for the atomic mass of indium are obtained using these two formulas? Assume that oxygen has an atomic mass of 16.00 .
From the information in this chapter on the mass of the proton, the mass of the electron, and the sizes of the nucleus and the atom, calculate the densities of a hydrogen nucleus and a hydrogen atom.
If you wanted to make an accurate scale model of the hydrogen atom and decided that the nucleus would have a diameter of 1 mm, what would be the diameter of the entire model?
In an experiment it was found that the total charge on an oil drop was $5.93 \times 10^{-18} \mathrm{C}$ . How many negative charges does the drop contain?
A chemist in a galaxy far, far away performed the Millikan oil drop experiment and got the following results for the charges on various drops. Use these data to calculate the charge of the electron in zirkombs.$\begin{array}{ll}{2.56 \times 10^{-12} \text { zirkombs }} & {7.68 \times 10^{-12} \text { zirkombs }} \\ {3.84 \times 10^{-12} \text { zirkombs }} & {6.40 \times 10^{-13} \text { zirkombs }}\end{array}$
Give the names of the metals that correspond to the following symbols: Sn, Pt, Hg, Mg, K, Ag.
What are the symbols of the following nonmetals: fluorine, chlorine, bromine, sulfur, oxygen,phosphorus?
In the periodic table, how many elements are found in each of the following?a. Group 2Ab. the oxygen familyc. the nickel groupd. Group 8A
In the periodic table, how many elements are found in each of the following?a. the halogen familyb. the alkali familyc. the lanthanide series
a. Classify the following elements as metals or nonmetals:$$\begin{array}{lll}\mathrm{Mg} & \mathrm{Si} & \mathrm{Rn} \\ \mathrm{Ti} & \mathrm{Ge} & \mathrm{Eu} \\ \mathrm{Au} & \mathrm{B} & \mathrm{Am} \\ \mathrm{Bi} & \mathrm{At} & \mathrm{Br}\end{array}$$b. The distinction between metals and nonmetals is really not a clear one. Some elements, called metalloids, are intermediate in their properties. Which of these elements would you reclassify as metalloids? What other elements in the periodic table would you expect to be metalloids?
a. Classify the following elements as metals or nonmetals:$\begin{array}{lll}{\mathrm{Mg}} & {\mathrm{Si}} & {\mathrm{Rn}} \\ {\mathrm{Ti}} & {\mathrm{Ge}} & {\mathrm{Eu}} \\ {\mathrm{Au}} & {\mathrm{B}} & {\mathrm{Am}} \\ {\mathrm{Bi}} & {\mathrm{At}} & {\mathrm{Br}}\end{array}$b. The distinction between metals and nonmetals is really not a clear one. Some elements, called metalloids, are intermediate in their properties. Which of these elements would you reclassify as metalloids? What other elements in the periodic table would you expect to be metalloids?
a. List the noble gas elements. Which of the noble gases has only radioactive isotopes? (This situation is indicated on most periodic tables by parentheses around the mass of the element. See inside front cover.)b. Which lanthanide element has only radioactive isotopes?
For each of the following sets of elements, label each as either noble gases, halogens, alkali metals, alkaline earth metals, or transition metals.a. Ti, Fe, Agb. Mg, Sr, Bac. Li, K, Rbd. Ne, Kr, Xee. F, Br, I
Identify the elements that correspond to the following atomic numbers. Label each as either a noble gas, a halogen, an alkali metal, an alkaline earth metal, a transition metal, a lanthanide metal, or an actinide metal.a. 17b. 4c. 63d. 72e. 2f. 92g. 55
Write the atomic symbol $\left(_{Z}^{A} X\right)$ for each of the following isotopes.a. $Z=8,$ number of neutrons $=9$b. the isotope of chlorine in which $A=37$c. $Z=27, A=60$d. number of protons $=26,$ number of neutrons $=31$e. the isotope of I with a mass number of 131f. $Z=3,$ number of neutrons $=4$
Write the atomic symbol $\left(_{Z}^{A} X\right)$ for each of the isotopes described below.a. number of protons $=27,$ number of neutrons $=31$b. the isotope of boron with mass number 10c. $Z=12, A=23$d. atomic number $53,$ number of neutrons $=79$e. $Z=20$ , number of neutrons $=27$f. number of protons $=29,$ mass number 65
Write the symbol of each atom using the $\left(_{Z}^{A} X\right)$ format.
For carbon-14 and carbon-12, how many protons and neutrons are in each nucleus? Assuming neutral atoms, how many electrons are present in an atom of carbon-14 and in an atom of carbon-12?
How many protons and neutrons are in the nucleus of each of the following atoms? In a neutral atom of each element, how many electrons are present?a. $^{79} \mathrm{Br}$b. $^{81} \mathrm{Br}$c. $^{239} \mathrm{Pu}$d. $^{133} \mathrm{Cs}$e. $^{3} \mathrm{H}$f. $^{56} \mathrm{Fe}$
What number of protons and neutrons are contained in the nucleus of each of the following atoms? Assuming each atom is uncharged, what number of electrons are present?a. $^{235}_{92} \mathrm{U}$b. $_{13}^{27} \mathrm{Al}$c. $_{26}^{57} \mathrm{Fe}$d. $_{82}^{208} \mathrm{Pb}$e. $_{37}^{86} \mathrm{Rb}$f. $_{20}^{41} \mathrm{Ca}$
For each of the following ions, indicate the number of protons and electrons the ion contains.a. $\quad \mathrm{Ba}^{2+}$b. $\mathrm{Zn}^{2+}$c. $\mathrm{N}^{3-}$d. $\mathrm{Rb}^{+}$e. $\mathrm{Co}^{3+}$f. $\mathrm{Te}^{2-}$g. $\mathrm{Br}^{-}$
How many protons, neutrons, and electrons are in each of the following atoms or ions?a. $_{12}^{24} \mathrm{Mg}$b. $_{12}^{24} \mathrm{Mg}^{2+}$c. $_{27}^{59} \mathrm{Co}^{2+}$d. $_{27}^{59} \mathrm{Co}^{3+}$e. $_{2}^{59} \mathrm{Co}$f. $_{34}^{79} \mathrm{Se}$g. $_{34}^{79} \mathrm{Se}^{2-}$h. $_{28}^{63} \mathrm{Ni}$i. $_{28}^{59} \mathrm{Ni}^{2+}$
What is the symbol for an ion with 63 protons, 60 electrons, and 88 neutrons? If an ion contains 50 protons, 68 neutrons, and 48 electrons, what is its symbol?
What is the symbol of an ion with 16 protons, 18 neutrons, and 18 electrons? What is the symbol for an ion that has 16 protons, 16 neutrons, and 18 electrons?
Complete the following table:
Would you expect each of the following atoms to gain or lose electrons when forming ions? What ion is the most likely in each case?a. Ra b. Inc. Pd. Tee. Brf. Rb
For each of the following atomic numbers, use the periodic table to write the formula (including the charge) for the simple ion that the element is most likely to form in ionic compounds.a. 13b. 34c. 56d. 7e. 87f. 35
Name the compounds in parts a–d and write the formulas for the compounds in parts e–h.a. $\operatorname{NaBr}$b. $\mathrm{Rb}_{2} \mathrm{O}$c. $\mathrm{CaS}$d. d. $\mathrm{AlI}_{3}$e. strontium fluoridef. aluminum selenideg. potassium nitrideh. magnesium phosphide
Name the compounds in parts a–d and write the formulas for the compounds in parts e–h.a. $\mathrm{Hg}_{2} \mathrm{O}$b. $\mathrm{FeBr}_{3}$c. $\mathrm{CoS}$d. $\mathrm{TiCl}_{4}$e. tin(II) nitridef. cobalt(III) iodideg. mercury(II) oxideh. chromium(VI) sulfide
Name each of the following compounds:a. $\mathrm{CsF}$b. b. $\mathrm{Li}_{3} \mathrm{N}$c. $\mathrm{Ag}_{2} \mathrm{S}$d. $\mathrm{MnO}_{2}$e. $\mathrm{TiO}_{2}$f. $\mathrm{Sr}_{3} \mathrm{P}_{2}$
Write the formula for each of the following compounds:a. zinc chlorideb. tin(IV) fluoridec. calcium nitrided. aluminum sulfidee. mercury(I) selenidef. silver iodide
Name each of the following compounds:a. $\mathrm{BaSO}_{3}$b. $\mathrm{NaNO}_{2}$c. $\mathrm{KMnO}_{4}$d. $\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}$
Write the formula for each of the following compounds:a. chromium(III) hydroxide b. magnesium cyanide c. lead(IV) carbonated. ammonium acetate
Name each of the following compounds:
Write the formula for each of the following compounds:a. diboron trioxideb. arsenic pentafluoridec. dinitrogen monoxided. sulfur hexachloride
Name each of the following compounds:a. Culb. $\mathrm{CuI}_{2}$c. $\mathrm{Col}_{2}$d. $\mathrm{Na}_{2} \mathrm{CO}_{3}$e. $\mathrm{NaHCO}_{3}$f. $\mathrm{S}_{4} \mathrm{N}_{4}$g. $\operatorname{SeCl}_{4}$h. $\mathrm{NaOCl}$i. $\mathrm{BaCrO}_{4}$j. $\mathrm{NH}_{4} \mathrm{NO}_{3}$
Name each of the following compounds. Assume the acids are dissolved in water.a. $\mathrm{HC}_{2} \mathrm{H}_{3} \mathrm{O}_{2}$b. $\mathrm{NH}_{4} \mathrm{NO}_{2}$c. $\mathrm{Co}_{2} \mathrm{S}_{3}$d. ICle. $\mathrm{Pb}_{3}\left(\mathrm{PO}_{4}\right)_{2}$f. $\mathrm{KClO}_{3}$g. $\mathrm{H}_{2} \mathrm{SO}_{4}$h. $\mathrm{Sr}_{3} \mathrm{N}_{2}$i. $\mathrm{Al}_{2}\left(\mathrm{SO}_{3}\right)_{3}$j. $\mathrm{SnO}_{2}$k. $\mathrm{Na}_{2} \mathrm{CrO}_{4}$I. HClo
Elements in the same family often form oxyanions of the same general formula. The anions are named in a similar fashion. What are the names of the oxyanions of selenium and tellurium:$\mathrm{SeO}_{4}^{2-}, \mathrm{SeO}_{3}^{2-}, \mathrm{TeO}_{4}^{2-}, \mathrm{TeO}_{3}^{2-} ?$
Knowing the names of similar chlorine oxyanions and acids, deduce the names of the following: $\mathrm{IO}^{-}, \mathrm{IO}_{2}^{-}, \mathrm{IO}_{3}^{-}, \mathrm{IO}_{4}^{-}$$\mathrm{HIO}, \mathrm{HIO}_{2}, \mathrm{HIO}_{3}, \mathrm{HIO}_{4}$
Write the formula for each of the following compounds:a. sulfur difluorideb. sulfur hexafluoridec. sodium dihydrogen phosphated. lithium nitridee. chromium(III) carbonatef. tin(II) fluorideg. ammonium acetateh. ammonium hydrogen sulfatei. cobalt(III) nitratej. mercury(I) chloridek. potassium chloratel. sodium hydride
Write the formula for each of the following compounds:a. chromium(VI) oxideb. disulfur dichloridec. nickel(II) fluorided. potassium hydrogen phosphatee. aluminum nitridef. ammoniag. manganese(IV) sulfideh. sodium dichromatei. ammonium sulfitej. carbon tetraiodide
Write the formula for each of the following compounds:a. sodium oxideb. sodium peroxidec. potassium cyanided. copper(II) nitratee. selenium tetrabromidef. iodous acidg. lead(IV) sulfideh. copper(I) chloridei. gallium arsenidej. cadmium selenidek. zinc sulfidel. nitrous acidm. diphosphorus pentoxide
Write the formula for each of the following compounds:a. ammonium hydrogen phosphateb. mercury(I) sulfidec. silicon dioxided. sodium sulfitee. aluminum hydrogen sulfatef. nitrogen trichlorideg. hydrobromic acidh. bromous acidi. perbromic acidj. potassium hydrogen sulfidek. calcium iodidel. cesium perchlorate
Name the acids illustrated below.
Each of the following compounds is incorrectly named. What is wrong with each name, and what is the correct name for each compound?a. $\mathrm{FeCl}_{3},$ iron chlorideb. $\mathrm{NO}_{2},$ nitrogen (IV) oxidec. CaO, calcium(Il) monoxided. $\mathrm{Al}_{2} \mathrm{S}_{3},$ dialuminum trisulfidee. $\operatorname{Mg}\left(\mathrm{C}_{2} \mathrm{H}_{3} \mathrm{O}_{2}\right)_{2},$ manganese diacetatef. $\mathrm{FePO}_{4},$ iron(II) phosphideg. $\mathrm{P}_{2} \mathrm{S}_{5}$ , phosphorus sulfideh. $\mathrm{Na}_{2} \mathrm{O}_{2},$ sodium oxidei. $\mathrm{HNO}_{3},$ nitrate acidj. $\mathrm{H}_{2} \mathrm{S},$ sulfuric acid
Insulin is a complex protein molecule produced by the pancreas in all vertebrates. It is a hormone that regulates carbohydrate metabolism. Inability to produce insulin results in diabetes mellitus. Diabetes is treated by injections of insulin. Given the law of definite proportion, would you expect there to be any differences in chemical activity between human insulin extracted from pancreatic tissue and human insulin produced by genetically engineered bacteria? Why or why not?
Carbohydrates, a class of compounds containing the elements carbon, hydrogen, and oxygen, were originally thought to contain one water $\left(\mathrm{H}_{2} \mathrm{O}\right)$ molecule for each carbon atom present. The carbohydrate glucose contains six carbon atoms. Write a general formula showing the relative numbers of each type of atom present in glucose.
Radiotracers are radioactive substances that can be introduced into organisms by way of ingestion or injection and whose pathway can be traced by monitoring their radioactivity. How many protons and neutrons do the following radiotracers contain?a. Iodine-131, used in the diagnosis and treatment of illnesses of the thyroid gland.b. Thallium-201, used to assess the damage to the heart muscle in a person who has suffered a heart attack.
What are the symbols for the following nonmetal elements that are most often present in compounds studied in organic chemistry: carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur? Predict a stable isotope for each of these elements.
Four $\mathrm{Fe}^{2+}$ ions are key components of hemoglobin, the protein that transports oxygen in the blood. Assuming that these ions are $^{53} \mathrm{Fe}^{2+},$ how many protons and neutrons are present in each nucleus, and how many electrons are present in each ion?
Which of the following statements is(are) true? For the false statements, correct them.a. All particles in the nucleus of an atom are charged.b. The atom is best described as a uniform sphere of matter in which electrons are embedded.c. The mass of the nucleus is only a very small fraction of the mass of the entire atom.d. The volume of the nucleus is only a very small fraction of the total volume of the atom.e. The number of neutrons in a neutral atom must equal the number of electrons.
The isotope of an unknown element, $X$ , hass a mass number of $79 .$ The most stable ion of the isotope has 36 electrons and forms a binary compound with sodium, having a formula of $\mathrm{Na}_{2} \mathrm{X}$ . Which of the following statements is (are) true? For the false statements, correct them.a. The binary compound formed between X and fluorine will be a covalent compound.b. The isotope of X contains 38 protons.c. The isotope of X contains 41 neutrons.d. The identity of X is strontium, Sr.
For each of the following ions, indicate the total number of protons and electrons in the ion. For the positive ions in the list, predict the formula of the simplest compound formed between each positive ion and the oxide ion. Name the compounds. For the negative ions in the list, predict the formula ofthe simplest compound formed between each negative ion and the aluminum ion. Name the compounds.a. $\mathrm{Fe}^{2+}$b. $\mathrm{Fe}^{3+}$c. $\mathrm{Ba}^{2+}$d. $\mathrm{Cs}^{+}$e. $\mathrm{S}^{2-}$f. $\mathrm{P}^{3-}$g. $\mathrm{Br}^{-}$h. $\mathrm{N}^{3-}$
The formulas and common names for several substances are given below. Give the systematic names for these substances.a. sugar of lead $\quad \operatorname{Pb}\left(\mathrm{C}_{2} \mathrm{H}_{3} \mathrm{O}_{2}\right)_{2}$b. blue vitrol $\quad$ CuSO $_{4}$c. quicklime $\quad \mathrm{CaO}$d. Epsom salts $\quad\mathrm{MgSO}_{4}$e. milk of magnesia $\quad \operatorname{Mg}(\mathrm{OH})_{2}$f. gypsum $\quad \mathrm{CaSO}_{4}$g. laughing gas $\quad \mathrm{N}_{2} \mathrm{O}$
Identify each of the following elements:a. a member of the same family as oxygen whose most stable ion contains 54 electronsb. a member of the alkali metal family whose most stable ion contains 36 electronsc. a noble gas with 18 protons in the nucleusd. a halogen with 85 protons and 85 electrons
An element's most stable ion forms an ionic compound with bromine, having the formula $\mathrm{XBr}_{2}$ . If the ion of element $\mathrm{X}$ has a mass number of 230 and has 86 electrons, what is the identity of the element, and how many neutrons does it have?
A certain element has only two naturally occurring isotopes: one with 18 neutrons and the other with 20 neutrons. The element forms $1-$ charged ions when in ionic compounds. Predict the identity of the element. What number of electrons does the $1-$ charged ion have?
The designations 1A through 8A used for certain families of the periodic table are helpful for predicting the charges on ions in binary ionic compounds. In these compounds, the metals generally take on a positive charge equal to the family number, while the nonmetals take on a negative charge equal to the family number minus eight. Thus the compound between sodium and chlorine contains $\mathrm{Na}^{+}$ ions and $\mathrm{Cl}^{-}$ ions and has the formula NaCl. Predict the formula and the name of the binary compound formed from the following pairs of elements.a. Ca and Nb. $\mathrm{K}$ and $\mathrm{O}$c. $\mathrm{Rb}$ and $\mathrm{F}$d. Mg and Se. Ba and If. Al and Seg. $\mathrm{Cs}$ and $\mathrm{P}$h. In and Br
By analogy with phosphorus compounds, name the following: $\mathrm{Na}_{3} \mathrm{AsO}_{4}, \mathrm{H}_{3} \mathrm{AsO}_{4}, \mathrm{Mg}_{3}\left(\mathrm{SbO}_{4}\right)_{2}$
Identify each of the following elements. Give the number of protons and neutrons in each nucleus.a. $_{15}^{31} \mathrm{X}$b.$^{127}_{53} \mathrm{X}$c. $_{19}^{39} \mathrm{X}$d. $\stackrel{173}{70} \mathrm{X}$
In a reaction, 34.0 g of chromium(III) oxide reacts with 12.1 g of aluminum to produce chromium and aluminum oxide. If 23.3 g of chromium is produced, what mass of aluminum oxide is produced?
Consider 100.0 -g samples of two different compounds consisting only of carbon and oxygen. One compound contains 27.2 $\mathrm{g}$ of carbon, and the other has 42.9 $\mathrm{g}$ of carbon. How can these data support the law of multiple proportions if 42.9 is not a multiple of 27.2$?$ Show that these data support the law of multiple proportions.
Give the systematic name for the following compounds that are found in everyday life:a. $\mathrm{H}_{2} \mathrm{S}$ (rotten egg smell)b. $\mathrm{SO}_{2}$ (smell of burnt matches)c. $\mathrm{SF}_{6}$ (aerosol can propellant)d. $\mathrm{Na}_{2} \mathrm{SO}_{3}$ (dried fruit preservative)
Complete the following table, including the mass number and the atomic number, with the symbol for the isotope.
Complete the following table.
Which of the following is(are) correct?a. $^{40} \mathrm{Ca}^{2+}$ contains 20 protons and 18 electrons.b. Rutherford created the cathode-ray tube and was the founder of the charge-to-mass ratio of an electron.c. An electron is heavier than a proton.d. The nucleus contains protons, neutrons, and electrons
What are the formulas of the compounds that correspond to the names given in the following table?
What are the names of the compounds that correspond to the formulas given in the following table?
Complete the following table to predict whether the given atom will gain or lose electrons in forming the ion most likely to form when in ionic compounds.
Which of the following statements is(are) correct?a. The symbols for the elements magnesium, aluminum, and xenon are Mn, Al, and Xe, respectively.b. The elements $P,$ As, and $B$ i are in the same family on the periodic table.c. All of the following elements are expected to gain electrons to form ions in ionic compounds: Ga, Se, and Br.d. The elements $\mathrm{Co},$ Ni, and Hg are all transition elements.e. The correct name for $\mathrm{TiO}_{2}$ is titanium dioxide.
The elements in one of the groups in the periodic table are often called the coinage metals. Identify the elements in this group based on your own experience
Reaction of 2.0 $\mathrm{L}$ of hydrogen gas with 1.0 $\mathrm{L}$ of oxygen gas yields 2.0 $\mathrm{L}$ of water vapor. All gases are at the same temperature and pressure. Show how these data support the idea that oxygen gas is a diatomic molecule. Must we consider hydrogen to be a diatomic molecule to explain these results?
A combustion reaction involves the reaction of a substance with oxygen gas. The complete combustion of any hydrocarbon (binary compound of carbon and hydrogen) produces carbon dioxide and water as the only products. Octane is a hydrocarbon that is found in gasoline. Complete combustion of octane produces 8 L of carbon dioxide for every 9 L of water vapor (both measured at the same temperature and pressure). What is the ratio of carbon atoms to hydrogen atoms in a molecule of octane?
A chemistry instructor makes the following claim: “Consider that if the nucleus were the size of a grape, the electrons would be about 1 mile away on average.” Is this claim reasonably accurate? Provide mathematical support.
The early alchemists used to do an experiment in which water was boiled for several days in a sealed glass container. Eventually, some solid residue would appear in the bottom of the flask, which was interpreted to mean that some of the water in the flask had been converted into “earth.” When Lavoisierrepeated this experiment, he found that the water weighed the same before and after heating, and the mass of the flask plus the solid residue equaled the original mass of the flask. Were the alchemists correct? Explain what really happened. (This experiment is described in the article by A. F. Scott in Scientific American, January 1984.)
Consider the chemical reaction as depicted below. Label as much as you can using the terms atom, molecule, element, compound, ionic, gas, and solid.
Each of the following statements is true, but Dalton might have had trouble explaining some of them with his atomic theory. Give explanations for the following statements.a. The space-filling models for ethyl alcohol and dimethyl ether are shown below.These two compounds have the same composition by mass $(52 \% \text { carbon, } 13 \% \text { hydrogen, and } 35 \% \text { oxygen }),$ yet the two have different melting points, boiling points, andsolubilities in water.b. Burning wood leaves an ash that is only a small fraction of the mass of the original wood.c. Atoms can be broken down into smaller particles.d. One sample of lithium hydride is 87.4$\%$ lithium by mass, while another sample of lithium hydride is 74.9$\%$ lithium by mass. However, the two samples have the same chemical properties.
Each of the following statements is true, but Dalton might have had trouble explaining some of them with his atomic theory. Give explanations for the following statements.a. The space-filling models for ethyl alcohol and dimethyl ether are shown below.These two compounds have the same composition by mass $(52 \% \text { carbon, } 13 \% \text {hydrogen, and } 35 \% \text { oxygen }),$ yet the two have different melting points, boiling points, and solubilities in water.b. Burning wood leaves an ash that is only a small fraction of the mass of the original wood.c. Atoms can be broken down into smaller particles.d. One sample of lithium hydride is 87.4$\%$ lithium by mass, while another sample of lithium hydride is 74.9$\%$ lithium by mass. However, the two samples have the same chemical properties.
You have two distinct gaseous compounds made from element X and element Y. The mass percents are as follows:Compound I: $30.43 \% \mathrm{X}, 69.57 \% \mathrm{Y}$Compound $\mathrm{II} : 63.64 \% \mathrm{X}, 36.36 \% \mathrm{Y}$In their natural standard states, element X and element Y exist as gases. (Monatomic? Diatomic? Triatomic? That is for you to determine.) When you react “gas X” with “gas Y” to make the products, you get the following data (all at the same pressure and temperature):1 volume "gas $\mathrm{X}^{\prime \prime}+2$ volumes "gas $\mathrm{Y}^{\prime \prime} \longrightarrow$ 2 volumes compound I2 volumes $^{4}$ gas $\mathrm{X}^{\prime \prime}+1$ volume "gas $\mathrm{Y}^{\prime \prime} \longrightarrow$ 2 volumes compound IIAssume the simplest possible formulas for reactants and products in the chemical equations above. Then, determine the relative atomic masses of element X and element Y.
A single molecule has a mass of $7.31 \times 10^{-23}$ g. Provide an example of a real molecule that can have this mass. Assume the elements that make up the molecule are made of light isotopes where the number of protons equals the number of neutrons in the nucleus of each element.
You take three compounds, each consisting of two elements (X, Y, and/or Z), and decompose them to their respective elements. To determine the relative masses of X, Y, and Z, you collect and weigh the elements, obtaining the following data:a. What are the assumptions needed to solve this problem?b. What are the relative masses of X, Y, and Z?c. What are the chemical formulas of the three compounds?d. If you decompose 21 g of compound XY, how much of each element is present?
What is the systematic name of $\mathrm{Ta}_{2} \mathrm{O}_{5} ?$ If the charge on the metal remained constant and then sulfur was substituted for oxygen, how would the formula change? What is the difference in the total number of protons between $\mathrm{Ta}_{2} \mathrm{O}_{5}$ and its sulfur analog?
A binary ionic compound is known to contain a cation with 51 protons and 48 electrons. The anion contains one-third the number of protons as the cation. The number of electrons in the anion is equal to the number of protons plus 1. What is the formula of this compound? What is the name of this compound?
Using the information in Table $2.1,$ answer the following questions. In an ion with an unknown charge, the total mass of all the electrons was determined to be $2.55 \times 10^{-26} \mathrm{g},$ while the total mass of its protons was $5.34 \times 10^{-23}$ g. What is the identity and charge of this ion? What is the symbol and mass number of a neutral atom whose total mass of its electrons is $3.92 \times 10^{-26} \mathrm{g},$ while its neutrons have a mass of $9.35 \times 10^{-23} \mathrm{g} ?$
You have gone back in time and are working with Dalton on a table of relative masses. Following are his data.0.602 g gas A reacts with 0.295 g gas $\mathrm{B}$0.172 $\mathrm{g}$ gas $\mathrm{B}$ reacts with 0.401 $\mathrm{g}$ gas $\mathrm{C}$0.320 $\mathrm{g}$ gas A reacts with 0.374 $\mathrm{g}$ gas $\mathrm{C}$a. Assuming simplest formulas (AB, BC, and AC), construct a table of relative masses for Dalton.b. Knowing some history of chemistry, you tell Dalton that if he determines the volumes of the gases reacted at constant temperature and pressure, he need not assume simplest formulas. You collect the following data:6 volumes gas $\mathrm{A}+1$ volume gas $\mathrm{B} \rightarrow$ 4 volumes product1 volume gas $\mathrm{B}+4$ volumes gas $\mathrm{C} \rightarrow$ 4 volumes product3 volumes gas $\mathrm{A}+2$ volumes gas $\mathrm{C} \rightarrow$ 6 volumes productWrite the simplest balanced equations, and find the actual relative masses of the elements. Explain your reasoning.