Question 1

You are asked to indicate the type and number of atoms in a molecule. Which representation would work best?

Accepted Answer

A)  molecular formula 
B)  structural formula 
C)  ball-and-stick model 
D)  space-filling model 
A)  molecular formula 
B)  structural formula 
C)  ball-and-stick model 
D)  space-filling model A

Question 2

Carbon-14 has the same ________.

Accepted Answer

A)  atomic number and atomic mass as carbon-12 
B)  atomic number and thus number of neutrons as carbon-13 
C)  atomic mass as both carbon-12 and carbon-13 
D)  number of protons but more neutrons than carbon-12 
A)  atomic number and atomic mass as carbon-12 
B)  atomic number and thus number of neutrons as carbon-13 
C)  atomic mass as both carbon-12 and carbon-13 
D)  number of protons but more neutrons than carbon-12 D

Question 3

Which statement is true of all atoms that are anions?

Accepted Answer

A)  The atom has more electrons than protons. 
B)  The atom has more protons than electrons. 
C)  The atom has fewer protons than does a neutral atom of the same element. 
D)  The atom has more neutrons than protons. 
A)  The atom has more electrons than protons. 
B)  The atom has more protons than electrons. 
C)  The atom has fewer protons than does a neutral atom of the same element. 
D)  The atom has more neutrons than protons. A

Question 4

Atoms have no electric charge because they have ________.

Accepted Answer

A)  uncharged neutrons in their nuclei 
B)  an equal number of protons and neutrons 
C)  an equal number of protons and electrons 
D)  an equal number of charged and uncharged subatomic particles 
A)  uncharged neutrons in their nuclei 
B)  an equal number of protons and neutrons 
C)  an equal number of protons and electrons 
D)  an equal number of charged and uncharged subatomic particles

Question 5

What is the maximum number of covalent bonds that an oxygen atom with atomic number 8 can make with hydrogen?

Accepted Answer

A)  1 
B)  2 
C)  4 
D)  6 
A)  1 
B)  2 
C)  4 
D)  6

Question 6

Molybdenum has an atomic number of 42. Several common isotopes exist, with mass numbers from 92-100. Which of the following can be true?

Accepted Answer

A)  Molybdenum atoms can have between 50 and 58 neutrons. 
B)  Molybdenum atoms can have between 50 and 58 protons. 
C)  Molybdenum atoms can have between 50 and 58 electrons. 
D)  Isotopes of molybdenum have different numbers of electrons. 
A)  Molybdenum atoms can have between 50 and 58 neutrons. 
B)  Molybdenum atoms can have between 50 and 58 protons. 
C)  Molybdenum atoms can have between 50 and 58 electrons. 
D)  Isotopes of molybdenum have different numbers of electrons.

Question 7

Which of the following statements correctly describes any chemical reaction that has reached equilibrium?

Accepted Answer

A)  The concentrations of products and reactants are equal. 
B)  The reaction is now irreversible. 
C)  Both forward and reverse reactions have halted. 
D)  The rates of the forward and reverse reactions are equal. 
A)  The concentrations of products and reactants are equal. 
B)  The reaction is now irreversible. 
C)  Both forward and reverse reactions have halted. 
D)  The rates of the forward and reverse reactions are equal.

Question 8

If an atom has a charge of +1, which of the following must be true?

Accepted Answer

A)  It has two more protons than neutrons. 
B)  It has the same number of protons as electrons. 
C)  It has one more electron than it does protons. 
D)  It has one more proton than it does electrons. 
A)  It has two more protons than neutrons. 
B)  It has the same number of protons as electrons. 
C)  It has one more electron than it does protons. 
D)  It has one more proton than it does electrons.

Question 9

Which of the following factors will increase the rate of reaction in the forward direction?

Accepted Answer

A)  addition of nitrogen 
B)  addition of ammonia 
C)  addition of hydrogen 
D)  addition of both nitrogen and hydrogen 
A)  addition of nitrogen 
B)  addition of ammonia 
C)  addition of hydrogen 
D)  addition of both nitrogen and hydrogen

Question 10

What is the atomic number of the cation formed in the reaction in the illustration?

Accepted Answer

A)  8 
B)  10 
C)  11 
D)  16 
A)  8 
B)  10 
C)  11 
D)  16

Question 11

Elements 72Zn, 75As, and 74Ge have the ________.

Accepted Answer

A)  same number of protons 
B)  same number of protons and electrons 
C)  same number of neutrons 
D)  same number of neutrons and electrons 
A)  same number of protons 
B)  same number of protons and electrons 
C)  same number of neutrons 
D)  same number of neutrons and electrons

Question 12

Which pair of elements would likely have similar valency and thus similar chemical behaviour?

Accepted Answer

A)  nitrogen and phosphorus 
B)  carbon and nitrogen 
C)  sodium and chlorine 
D)  hydrogen and helium 
A)  nitrogen and phosphorus 
B)  carbon and nitrogen 
C)  sodium and chlorine 
D)  hydrogen and helium

Question 13

How many electrons are involved in a triple covalent bond?

Accepted Answer

A)  3 
B)  6 
C)  9 
D)  12 
A)  3 
B)  6 
C)  9 
D)  12

Question 14

When are atoms most stable?

Accepted Answer

A)  When they have the fewest possible valence electrons. 
B)  When they have the maximum number of unpaired electrons. 
C)  When all of the electron orbitals in the valence shell are filled. 
D)  When all electrons are paired. 
A)  When they have the fewest possible valence electrons. 
B)  When they have the maximum number of unpaired electrons. 
C)  When all of the electron orbitals in the valence shell are filled. 
D)  When all electrons are paired.

Question 15

Which of the following correctly describes chemical equilibrium?

Accepted Answer

A)  Forward and reverse reactions continue with no net effect on the concentrations of the reactants and products. 
B)  Concentrations of products are higher than the concentrations of the reactants. 
C)  There are equal concentrations of products and reactants while forward and reverse reactions continue. 
D)  There are equal concentrations of reactants and products, and the reactions have stopped. 
A)  Forward and reverse reactions continue with no net effect on the concentrations of the reactants and products. 
B)  Concentrations of products are higher than the concentrations of the reactants. 
C)  There are equal concentrations of products and reactants while forward and reverse reactions continue. 
D)  There are equal concentrations of reactants and products, and the reactions have stopped.

Question 16

Which of the following is the best description of an atom's physical structure?

Accepted Answer

A)  An atom is a solid mass of material. 
B)  The particles that form an atom are equidistant from each other. 
C)  Atoms are little bubbles of space with mass concentrated at the centre of the bubble. 
D)  Atoms are little bubbles of space with mass concentrated on the outside surface of the bubble. 
A)  An atom is a solid mass of material. 
B)  The particles that form an atom are equidistant from each other. 
C)  Atoms are little bubbles of space with mass concentrated at the centre of the bubble. 
D)  Atoms are little bubbles of space with mass concentrated on the outside surface of the bubble.

Question 17

A covalent bond is likely to be polar when ________.

Accepted Answer

A)  one of the atoms sharing electrons is more electronegative than the other atom 
B)  the two atoms sharing electrons are equally electronegative 
C)  carbon is one of the two atoms sharing electrons 
D)  the two atoms sharing electrons are of the same elements 
A)  one of the atoms sharing electrons is more electronegative than the other atom 
B)  the two atoms sharing electrons are equally electronegative 
C)  carbon is one of the two atoms sharing electrons 
D)  the two atoms sharing electrons are of the same elements

Question 18

The reactivity of an atom arises from

Accepted Answer

A)  the average distance of the outermost electron shell from the nucleus. 
B)  the existence of unpaired electrons in the valence shell. 
C)  the sum of the potential energies of all the electron shells. 
D)  the potential energy of the valence shell. 
A)  the average distance of the outermost electron shell from the nucleus. 
B)  the existence of unpaired electrons in the valence shell. 
C)  the sum of the potential energies of all the electron shells. 
D)  the potential energy of the valence shell.

Question 19

The left to right order of elements in the periodic table is based on their ________.

Accepted Answer

A)  atomic mass 
B)  atomic number 
C)  electric charge of the atom 
D)  the number of neutrons 
A)  atomic mass 
B)  atomic number 
C)  electric charge of the atom 
D)  the number of neutrons

Question 20

What results from the chemical reaction in the illustration? The reactants have no charge.

Accepted Answer

A)  a cation with a net charge of +1 and an anion with a net charge of +1 
B)  a cation with a net charge of -1 and an anion with a net charge of -1 
C)  a cation with a net charge of -1 and an anion with a net charge of +1 
D)  a cation with a net charge of +1 and an anion with a net charge of -1 
A)  a cation with a net charge of +1 and an anion with a net charge of +1 
B)  a cation with a net charge of -1 and an anion with a net charge of -1 
C)  a cation with a net charge of -1 and an anion with a net charge of +1 
D)  a cation with a net charge of +1 and an anion with a net charge of -1

Exam 2: The Chemical Context of Life

You are asked to indicate the type and number of atoms in a molecule. Which representation would work best?

Carbon-14 has the same ________.

Which statement is true of all atoms that are anions?

Atoms have no electric charge because they have ________.

What is the maximum number of covalent bonds that an oxygen atom with atomic number 8 can make with hydrogen?

Molybdenum has an atomic number of 42. Several common isotopes exist, with mass numbers from 92-100. Which of the following can be true?

Which of the following statements correctly describes any chemical reaction that has reached equilibrium?

If an atom has a charge of +1, which of the following must be true?

Which of the following factors will increase the rate of reaction in the forward direction?

What is the atomic number of the cation formed in the reaction in the illustration?

Elements 72Zn, 75As, and 74Ge have the ________.

Which pair of elements would likely have similar valency and thus similar chemical behaviour?

How many electrons are involved in a triple covalent bond?

When are atoms most stable?

Which of the following correctly describes chemical equilibrium?

Which of the following is the best description of an atom's physical structure?

A covalent bond is likely to be polar when ________.

The reactivity of an atom arises from

The left to right order of elements in the periodic table is based on their ________.

What results from the chemical reaction in the illustration? The reactants have no charge.

Evolution, the Themes of Biology, and Scientific Inquiry

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

Gene Expression: From Gene to Protein

Regulation of Gene Expression

Viruses

Dna Tools and Biotechnology

Genomes and Their Evolution

Descent With Modification: a Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonised Land

Plant Diversity Ii: the Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Vascular Plant Structure, Growth, and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons, Synapses, and Signalling

Nervous Systems

Sensory and Motor Mechanisms

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