Question 1

Which one of the following statements about atoms and subatomic particles is correct?

Accepted Answer

A)  Rutherford discovered the atomic nucleus by bombarding gold foil with electrons. 
B)  The proton and the neutron have identical masses. 
C)  The neutron's mass is equal to that of a proton plus an electron. 
D)  A neutral atom contains equal numbers of protons and electrons. 
E)  An atomic nucleus contains equal numbers of protons and neutrons. 
A)  Rutherford discovered the atomic nucleus by bombarding gold foil with electrons. 
B)  The proton and the neutron have identical masses. 
C)  The neutron's mass is equal to that of a proton plus an electron. 
D)  A neutral atom contains equal numbers of protons and electrons. 
E)  An atomic nucleus contains equal numbers of protons and neutrons.

Question 2

Which one of the following combinations of names and formulas of ions is incorrect?

Accepted Answer

A)  O2- oxide 
B)  Cd2+ cadmium 
C)  ClO3- chlorate 
D)  HCO3- hydrogen carbonate 
E)  NO2- nitrate 
A)  O2- oxide 
B)  Cd2+ cadmium 
C)  ClO3- chlorate 
D)  HCO3- hydrogen carbonate 
E)  NO2- nitrate

Question 3

J. J. Thomson studied cathode ray particles (electrons) and was able to measure the mass/charge ratio. His results showed that

Accepted Answer

A)  the mass/charge ratio varied with as the cathode material was changed. 
B)  the charge was always a whole-number multiple of some minimum charge. 
C)  matter included particles much smaller than the atom. 
D)  atoms contained dense areas of positive charge. 
E)  atoms are largely empty space. 
A)  the mass/charge ratio varied with as the cathode material was changed. 
B)  the charge was always a whole-number multiple of some minimum charge. 
C)  matter included particles much smaller than the atom. 
D)  atoms contained dense areas of positive charge. 
E)  atoms are largely empty space.

Question 4

Which one of the following is a polyatomic cation?

Accepted Answer

A)  nitrate 
B)  chromate 
C)  permanganate 
D)  hydronium 
E)  potassium 
A)  nitrate 
B)  chromate 
C)  permanganate 
D)  hydronium 
E)  potassium

Question 5

Ammonium sulfate, (NH4)2SO4, is a fertilizer widely used as a source of nitrogen. Calculate its molecular mass.

Accepted Answer

A)  63.07 amu 
B)  114.10 amu 
C)  118.13 amu 
D)  128.11 amu 
E)  132.13 amu 
A)  63.07 amu 
B)  114.10 amu 
C)  118.13 amu 
D)  128.11 amu 
E)  132.13 amu

Question 6

The formula of heptane is

Accepted Answer

A)  C6H12. 
B)  C6H14. 
C)  C7H14. 
D)  C7H16. 
E)  C8H16. 
A)  C6H12. 
B)  C6H14. 
C)  C7H14. 
D)  C7H16. 
E)  C8H16.

Question 7

Diiodine pentaoxide is used as an oxidizing agent that converts carbon monoxide to carbon dioxide. What is its chemical formula?

Accepted Answer

A)  I2O5 
B)  IO5 
C)  2IO5 
D)  I5O2 
E)  (IO5)2 
A)  I2O5 
B)  IO5 
C)  2IO5 
D)  I5O2 
E)  (IO5)2

Question 8

Kaolinite, a clay mineral with the formula Al4Si4O10(OH)8, is used as a filler in slick-paper for magazines and as a raw material for ceramics. Analysis shows that 14.35 g of kaolinite contains 8.009 g of oxygen. Calculate the mass percent of oxygen in kaolinite.

Accepted Answer

A)  1.792 mass % 
B)  24.80 mass % 
C)  30.81 mass % 
D)  34.12 mass % 
E)  55.81 mass % 
A)  1.792 mass % 
B)  24.80 mass % 
C)  30.81 mass % 
D)  34.12 mass % 
E)  55.81 mass %

Question 9

Dalton's atomic theory has required some modifications in the light of subsequent discoveries. For any three appropriate postulates of Dalton's atomic theory
a. state the postulate in its original form.
b. in one sentence, describe why the postulate has needed modification.

Accepted Answer

1. Matter consists of atoms which are in

Question 10

Calcium hydroxide is used in mortar, plaster, and cement. What is its formula?

Accepted Answer

A)  CaOH 
B)  CaOH2 
C)  Ca2OH 
D)  Ca(OH)2 
E)  CaHO2 
A)  CaOH 
B)  CaOH2 
C)  Ca2OH 
D)  Ca(OH)2 
E)  CaHO2

Question 11

The mass of a neutron is equal to the mass of a proton plus the mass of an electron.

Accepted Answer

A) True 
 B)False

Question 12

Determine the molecular mass of iron (III) bromide hexahydrate, a substance used as a catalyst in organic reactions.

Accepted Answer

A)  403.65 amu 
B)  355.54 amu 
C)  317.61 amu 
D)  313.57 amu 
E)  295.56 amu 
A)  403.65 amu 
B)  355.54 amu 
C)  317.61 amu 
D)  313.57 amu 
E)  295.56 amu

Question 13

State the two important experimental results (and the names of the responsible scientists) which enabled the mass of the electron to be determined.

Accepted Answer

Thomson measured m/e, the mass

Question 14

Modern studies have shown that the Law of Multiple Proportions is not valid.

Accepted Answer

A) True 
 B)False

Question 15

What are the approximate carbon:hydrogen mass ratios in methane (CH4) and ethyne (C2H2)?

Accepted Answer

A)  1:4 and 1:1 
B)  3:2 and 6:1 
C)  3:1 and 12:1 
D)  3:2 and 12:1 
E)  3:1 and 6:1 
A)  1:4 and 1:1 
B)  3:2 and 6:1 
C)  3:1 and 12:1 
D)  3:2 and 12:1 
E)  3:1 and 6:1

Question 16

What is the name of the acid formed when H2S gas is dissolved in water?

Accepted Answer

A)  sulfuric acid 
B)  sulfurous acid 
C)  hydrosulfuric acid 
D)  hydrosulfurous acid 
E)  sulfidic acid 
A)  sulfuric acid 
B)  sulfurous acid 
C)  hydrosulfuric acid 
D)  hydrosulfurous acid 
E)  sulfidic acid

Question 17

Lithium forms compounds which are used in dry cells and storage batteries and in high-temperature lubricants. It has two naturally occurring isotopes, 6Li (isotopic mass = 6.015121 amu) and 7Li (isotopic mass = 7.016003 amu). Lithium has an atomic mass of 6.9409 amu. What is the percent abundance of lithium-6?

Accepted Answer

A)  92.50% 
B)  86.66% 
C)  46.16% 
D)  7.503% 
E)  6.080% 
A)  92.50% 
B)  86.66% 
C)  46.16% 
D)  7.503% 
E)  6.080%

Question 18

Which of the following is a metal?

Accepted Answer

A)  nitrogen, N, Z = 7 
B)  phosphorus, P, Z = 15 
C)  arsenic, Z = 33 
D)  thallium, Tl, Z = 81 
E)  silicon, Si, Z = 14 
A)  nitrogen, N, Z = 7 
B)  phosphorus, P, Z = 15 
C)  arsenic, Z = 33 
D)  thallium, Tl, Z = 81 
E)  silicon, Si, Z = 14

Question 19

In the modern periodic table, the order in which the elements are placed is based on

Accepted Answer

A)  atomic mass. 
B)  mass number. 
C)  atomic number. 
D)  atomic size. 
E)  chemical reactivity. 
A)  atomic mass. 
B)  mass number. 
C)  atomic number. 
D)  atomic size. 
E)  chemical reactivity.

Question 20

For each of the following elements, indicate whether it is a metal, a non-metal, or a metalloid:
a. S
b. Ge
c. g
d. H
e. I
f. Si

Accepted Answer

a. nonmetal
b. metal

Exam 2: The Components of Matter

Which one of the following statements about atoms and subatomic particles is correct?

Which one of the following combinations of names and formulas of ions is incorrect?

J. J. Thomson studied cathode ray particles (electrons) and was able to measure the mass/charge ratio. His results showed that

Which one of the following is a polyatomic cation?

Ammonium sulfate, (NH4)2SO4, is a fertilizer widely used as a source of nitrogen. Calculate its molecular mass.

The formula of heptane is

Diiodine pentaoxide is used as an oxidizing agent that converts carbon monoxide to carbon dioxide. What is its chemical formula?

Kaolinite, a clay mineral with the formula Al4Si4O10(OH)8, is used as a filler in slick-paper for magazines and as a raw material for ceramics. Analysis shows that 14.35 g of kaolinite contains 8.009 g of oxygen. Calculate the mass percent of oxygen in kaolinite.

Dalton's atomic theory has required some modifications in the light of subsequent discoveries. For any three appropriate postulates of Dalton's atomic theory a. state the postulate in its original form. b. in one sentence, describe why the postulate has needed modification.

Calcium hydroxide is used in mortar, plaster, and cement. What is its formula?

The mass of a neutron is equal to the mass of a proton plus the mass of an electron.

Determine the molecular mass of iron (III) bromide hexahydrate, a substance used as a catalyst in organic reactions.

State the two important experimental results (and the names of the responsible scientists) which enabled the mass of the electron to be determined.

Modern studies have shown that the Law of Multiple Proportions is not valid.

What are the approximate carbon:hydrogen mass ratios in methane (CH4) and ethyne (C2H2)?

What is the name of the acid formed when H2S gas is dissolved in water?

Which of the following is a metal?

In the modern periodic table, the order in which the elements are placed is based on

For each of the following elements, indicate whether it is a metal, a non-metal, or a metalloid: a. S b. Ge c. g d. H e. I f. Si

Keys to the Study of Chemistry

Stoichiometry of Formulas and Equations

The Major Classes of Chemical Reactions

Gases and the Kinetic-Molecular Theory

Thermochemistry: Energy Flow and Chemical Change

Quantum Theory and Atomic Structure

Electron Configuration and Chemical Periodicity

Models of Chemical Bonding

The Shapes of Molecules

Theories of Covalent Bonding

Intermolecular Forces: Liquids, Solids, and Phase Changes

The Properties of Mixtures: Solutions and Colloids

Periodic Patterns in the Main Group Elements: Bonding, Structure, and Reactivity

Organic Compounds and the Atomic Properties of Carbon

Kinetics: Rates and Mechanisms of Chemical Reactions

Equilibrium: the Extent of Chemical Reactions

Acid-Base Equilibria

Ionic Equilibria in Aqueous Systems

Thermodynamics: Entropy, Free Energy, and the Direction of Chemical Reactions

Electrochemistry: Chemical Change and Electrical Work

The Elements in Nature and Industry

The Transition Elements and Their Coordination Compounds

Nuclear Reactions and Their Applications

Filters

Ammonium sulfate, (NH₄)₂SO₄, is a fertilizer widely used as a source of nitrogen. Calculate its molecular mass.

Kaolinite, a clay mineral with the formula Al₄Si₄O₁₀(OH)₈, is used as a filler in slick-paper for magazines and as a raw material for ceramics. Analysis shows that 14.35 g of kaolinite contains 8.009 g of oxygen. Calculate the mass percent of oxygen in kaolinite.

What are the approximate carbon:hydrogen mass ratios in methane (CH₄) and ethyne (C₂H₂)?

What is the name of the acid formed when H₂S gas is dissolved in water?