Question 1

All atoms of a given element are identical.

Accepted Answer

A) True 
 B)False

Question 2

A certain element contains eleven atoms of mass 95.952 u for every four atoms of mass 98.949 u. Compute the average atomic weight of this element.

Accepted Answer

A)  97.451 u 
B)  96.754 u 
C)  98.150 u 
D)  105.16 u 
E)  96.952 u 
A)  97.451 u 
B)  96.754 u 
C)  98.150 u 
D)  105.16 u 
E)  96.952 u

Question 3

Which statement below is true?

Accepted Answer

A)  Metals gain electrons to have a positive charge. 
B)  Metals gain electrons to have a negative charge. 
C)  Metals lose electrons to have a positive charge. 
D)  Nonmetals lose electrons. 
E)  Transition metals can gain 2 or more electrons to become metal ions. 
A)  Metals gain electrons to have a positive charge. 
B)  Metals gain electrons to have a negative charge. 
C)  Metals lose electrons to have a positive charge. 
D)  Nonmetals lose electrons. 
E)  Transition metals can gain 2 or more electrons to become metal ions.

Question 4

When decomposed chemically, 73.0 grams of a sample of HCl produce 71.0 g of Cl2 and 2.0 g of H2, while 34.0 g of a sample of H2S produce 32.0 g of S and 2.0 g of H2. This is an example of the Law:

Accepted Answer

A)  of Conservation of Mass 
B)  of Multiple Proportions 
C)  of Definite Proportions 
D)  E = mc2 
E)  of Simple Whole Numbers 
A)  of Conservation of Mass 
B)  of Multiple Proportions 
C)  of Definite Proportions 
D)  E = mc2 
E)  of Simple Whole Numbers

Question 5

Which of the following is a correct feature of the nuclear atom proposed by Rutherford?

Accepted Answer

A)  All atoms of an element have the same mass. 
B)  The atom is mostly empty space. 
C)  The number of neutrons and electrons in the atom are equal. 
D)  The majority of alpha particles to strike the foil "bounced back." 
E)  It is like the "plum pudding" model. 
A)  All atoms of an element have the same mass. 
B)  The atom is mostly empty space. 
C)  The number of neutrons and electrons in the atom are equal. 
D)  The majority of alpha particles to strike the foil "bounced back." 
E)  It is like the "plum pudding" model.

Question 6

Robert Millikan determined the charge on an electron.

Accepted Answer

A) True 
 B)False

Question 7

Choose the INCORRECT statement from those given below.

Accepted Answer

A)  Atoms retain their identity during a chemical reaction. 
B)  All matter is composed of atoms. 
C)  Atoms combine in small, whole-numbered ratios. 
D)  All atoms of a given element are identical. 
E)  Different ratios of atoms produce different compounds. 
A)  Atoms retain their identity during a chemical reaction. 
B)  All matter is composed of atoms. 
C)  Atoms combine in small, whole-numbered ratios. 
D)  All atoms of a given element are identical. 
E)  Different ratios of atoms produce different compounds.

Question 8

Lead-204 has a relative abundance of 1.48%. What size block of lead (in cubic centimeters) will contain 8.34 × 1021 atoms of lead-204? The density of lead is 11.35 g/cm3.

Accepted Answer

A)  3.75 × 10-3 
B)  0.253 
C)  194 
D)  17.1 
E)  16.8 
A)  3.75 × 10-3 
B)  0.253 
C)  194 
D)  17.1 
E)  16.8

Question 9

The following ratios of masses were obtained with a mass spectrometer:   /   = 1.8406,   /   = 1.5832 What is the mass of a   atom in atomic mass units?

Accepted Answer

A)  35.45 u 
B)  36.36 u 
C)  13.95 u 
D)  35.00 u 
E)  34.97 u 
A)  35.45 u 
B)  36.36 u 
C)  13.95 u 
D)  35.00 u 
E)  34.97 u

Question 10

How many Cu atoms are present in a 75.0 cm length of 20-gauge copper wire? A 20-gauge wire has a diameter of 0.03196 in. Copper's density is 8.92 g/cm3.

Accepted Answer

A)  1.31 × 1021 
B)  3.28 × 1022 
C)  8.08 × 1021 
D)  1.04 × 1022 
E)  2.08 × 1022 
A)  1.31 × 1021 
B)  3.28 × 1022 
C)  8.08 × 1021 
D)  1.04 × 1022 
E)  2.08 × 1022

Question 11

Dalton's atomic theory is based on several assumptions, which are listed below. Which of these assumptions is strictly correct? I) All atoms of the same element are identical.
II) Atoms are indivisible and unchangeable.
III) Chemical changes are the result of the combination, separation, and rearrangement of atoms.

Accepted Answer

A)  I, II, and III are correct. 
B)  I and III are correct. 
C)  II and III are correct. 
D)  I and II are correct. 
E)  III is correct. 
A)  I, II, and III are correct. 
B)  I and III are correct. 
C)  II and III are correct. 
D)  I and II are correct. 
E)  III is correct.

Question 12

How many atoms of rubidium-85 are in 87.2 g of rubidium? Rubidium-85 is 72.2 % abundant.

Accepted Answer

A)  5.16 × 1046 atoms 
B)  4.44 × 1023 atoms 
C)  8.51 × 1023 atoms 
D)  6.14 × 1022 atoms 
E)  1.02 × 1024 atoms 
A)  5.16 × 1046 atoms 
B)  4.44 × 1023 atoms 
C)  8.51 × 1023 atoms 
D)  6.14 × 1022 atoms 
E)  1.02 × 1024 atoms

Question 13

An isotope with mass number 81 has eleven more neutrons than protons. This is an isotope of what element?

Accepted Answer

A)  Tl 
B)  Yb 
C)  Zr 
D)  Br 
E)  Nb 
A)  Tl 
B)  Yb 
C)  Zr 
D)  Br 
E)  Nb

Question 14

Ernest Rutherford is credited with: I) the nuclear model of the atom
II) the identification of alpha and beta particles
III) the discovery of protons
IV) the prediction of a third, neutral, subatomic particle

Accepted Answer

A)  I and II 
B)  I and III 
C)  I, II, III 
D)  II, III, IV 
E)  I, II, III, IV 
A)  I and II 
B)  I and III 
C)  I, II, III 
D)  II, III, IV 
E)  I, II, III, IV

Question 15

Which of the following would be unaffected by an electric field?

Accepted Answer

A)  alpha particles 
B)  beta particles 
C)  gamma rays 
D)  protons 
E)  electrons 
A)  alpha particles 
B)  beta particles 
C)  gamma rays 
D)  protons 
E)  electrons

Question 16

Which of the following statements is true concerning the masses of individual Cl atoms?

Accepted Answer

A)  All atoms have a mass of 35.45 u. 
B)  Most of the atoms have a mass of 35.45 u. 
C)  Some of the atoms have a mass of 35.45 u. 
D)  None of the atoms have a mass of 35.45 u. 
E)  All atoms have a mass of 17 u. 
A)  All atoms have a mass of 35.45 u. 
B)  Most of the atoms have a mass of 35.45 u. 
C)  Some of the atoms have a mass of 35.45 u. 
D)  None of the atoms have a mass of 35.45 u. 
E)  All atoms have a mass of 17 u.

Question 17

How many protons, neutrons, and electrons are in   ?

Accepted Answer

A)  12 protons, 10 electrons, 12 neutrons 
B)  12 protons, 12 electrons, 12 neutrons 
C)  12 protons, 12 electrons, 24 neutrons 
D)  24 protons, 10 electrons, 12 neutrons 
E)  10 protons, 12 electrons, 24 neutrons 
A)  12 protons, 10 electrons, 12 neutrons 
B)  12 protons, 12 electrons, 12 neutrons 
C)  12 protons, 12 electrons, 24 neutrons 
D)  24 protons, 10 electrons, 12 neutrons 
E)  10 protons, 12 electrons, 24 neutrons

Question 18

Copper occurs in an isotopic mixture of 69.09% 63Cu (mass = 62.93 u per atom) and 30.91% 65Cu (mass = 64.93 u per atom). What is the average atomic mass of copper?

Accepted Answer

A)  64.00 u 
B)  63.55 u 
C)  63.45 u 
D)  64.31 u 
E)  29.00 u 
A)  64.00 u 
B)  63.55 u 
C)  63.45 u 
D)  64.31 u 
E)  29.00 u

Question 19

What is the isotopic atomic mass of an isotope if 9.7023 × 1022 atoms weighs 4.0256 g?

Accepted Answer

A)  0.64858 
B)  24.305 
C)  24.986 
D)  13.728 
E)  4.0256 
A)  0.64858 
B)  24.305 
C)  24.986 
D)  13.728 
E)  4.0256

Question 20

How many atoms of hydrogen are present in 1.5 lb of hydrogen peroxide, which is 5.93% hydrogen? (1 lb = 454 grams)

Accepted Answer

A)  2.4 × 1025 atoms 
B)  1.21 × 1025 atoms 
C)  1.2 × 1025 atoms 
D)  2.41 × 1025 atoms 
E)  1.2 × 1020 atoms 
A)  2.4 × 1025 atoms 
B)  1.21 × 1025 atoms 
C)  1.2 × 1025 atoms 
D)  2.41 × 1025 atoms 
E)  1.2 × 1020 atoms

Exam 2: Atoms and the Atomic Theory

All atoms of a given element are identical.

A certain element contains eleven atoms of mass 95.952 u for every four atoms of mass 98.949 u. Compute the average atomic weight of this element.

Which statement below is true?

When decomposed chemically, 73.0 grams of a sample of HCl produce 71.0 g of Cl2 and 2.0 g of H2, while 34.0 g of a sample of H2S produce 32.0 g of S and 2.0 g of H2. This is an example of the Law:

Which of the following is a correct feature of the nuclear atom proposed by Rutherford?

Robert Millikan determined the charge on an electron.

Choose the INCORRECT statement from those given below.

Lead-204 has a relative abundance of 1.48%. What size block of lead (in cubic centimeters) will contain 8.34 × 1021 atoms of lead-204? The density of lead is 11.35 g/cm3.

The following ratios of masses were obtained with a mass spectrometer: / = 1.8406, / = 1.5832 What is the mass of a atom in atomic mass units?

How many Cu atoms are present in a 75.0 cm length of 20-gauge copper wire? A 20-gauge wire has a diameter of 0.03196 in. Copper's density is 8.92 g/cm3.

How many atoms of rubidium-85 are in 87.2 g of rubidium? Rubidium-85 is 72.2 % abundant.

An isotope with mass number 81 has eleven more neutrons than protons. This is an isotope of what element?

Ernest Rutherford is credited with: I) the nuclear model of the atom II) the identification of alpha and beta particles III) the discovery of protons IV) the prediction of a third, neutral, subatomic particle

Which of the following would be unaffected by an electric field?

Which of the following statements is true concerning the masses of individual Cl atoms?

How many protons, neutrons, and electrons are in ?

Copper occurs in an isotopic mixture of 69.09% 63Cu (mass = 62.93 u per atom) and 30.91% 65Cu (mass = 64.93 u per atom). What is the average atomic mass of copper?

What is the isotopic atomic mass of an isotope if 9.7023 × 1022 atoms weighs 4.0256 g?

How many atoms of hydrogen are present in 1.5 lb of hydrogen peroxide, which is 5.93% hydrogen? (1 lb = 454 grams)

Matter - Its Properties and Measurement

Chemical Compounds

Chemical Reactions

Introduction to Reactions in Aqueous Solutions

Gases

Thermochemistry

Electrons in Atoms

The Periodic Table and Some Atomic Properties

Chemical Bonding I: Basic Concepts

Chemical Bonding II: Additional Aspects

Intermolecular Forces: Liquids and Solids

Solutions and Their Physical Properties

Chemical Kinetics

Principles of Chemical Equilibrium

Acids and Bases

Additional Aspects of Acid-Base Equilibria

Solubility and Complex-Ion Equilibria

Spontaneous Change: Entropy and Free Energy

Electrochemistry

Main Group Elements I: Groups 1, 2, 13, and 14

Main Group Elements II: Groups 18, 17, 16, 15, and Hydrogen

The Transition Elements

Complex Ions and Coordination Compounds

Nuclear Chemistry 1-41

Structures of Organic Compounds

Reactions of Organic Compounds

Chemistry of the Living State

Filters

When decomposed chemically, 73.0 grams of a sample of HCl produce 71.0 g of Cl₂ and 2.0 g of H₂, while 34.0 g of a sample of H₂S produce 32.0 g of S and 2.0 g of H₂. This is an example of the Law:

Lead-204 has a relative abundance of 1.48%. What size block of lead (in cubic centimeters) will contain 8.34 × 10²¹ atoms of lead-204? The density of lead is 11.35 g/cm3.

What is the isotopic atomic mass of an isotope if 9.7023 × 10²² atoms weighs 4.0256 g?