Question 1

Which of the following has the smallest total mass?

Accepted Answer

A)  two electrons 
B)  two neutrons 
C)  1 electron plus 1 neutron 
D)  1 neutron plus 1 proton 
A)  two electrons 
B)  two neutrons 
C)  1 electron plus 1 neutron 
D)  1 neutron plus 1 proton A

Question 2

Compared with 31P, the radioactive isotop 32P has ________.

Accepted Answer

A)  a different atomic number 
B)  one more proton 
C)  one more electron 
D)  one more neutron 
A)  a different atomic number 
B)  one more proton 
C)  one more electron 
D)  one more neutron D

Question 3

Van der Waals interactions may result under which of the following conditions?

Accepted Answer

A)  electrons are not symmetrically distributed in a molecule 
B)  molecules held by ionic bonds react with water 
C)  two polar covalent bonds react 
D)  a hydrogen atom loses an electron 
A)  electrons are not symmetrically distributed in a molecule 
B)  molecules held by ionic bonds react with water 
C)  two polar covalent bonds react 
D)  a hydrogen atom loses an electron A

Question 4

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.

Question 5

Nitrogen (N) is more electronegative than hydrogen (H). Which of the following is a correct statement about the atoms in ammonia (NH3)?

Accepted Answer

A)  Each hydrogen atom has a partial positive charge; the nitrogen atom has a partial negative charge. 
B)  Ammonia has an overall positive charge. 
C)  Ammonia has an overall negative charge. 
D)  The nitrogen atom has a partial positive charge; each hydrogen atom has a partial negative charge. 
A)  Each hydrogen atom has a partial positive charge; the nitrogen atom has a partial negative charge. 
B)  Ammonia has an overall positive charge. 
C)  Ammonia has an overall negative charge. 
D)  The nitrogen atom has a partial positive charge; each hydrogen atom has a partial negative charge.

Question 6

Under which of the following conditions will an atom be the 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 7

The atomic number of sulfur is 16. Sulfur combines with hydrogen by covalent bonding to form a compound, hydrogen sulfide. Based on the number of valence electrons in a sulfur atom, predict the molecular formula of the compound.

Accepted Answer

A)  HS 
B)  HS2 
C)  H2S 
D)  H4S 
A)  HS 
B)  HS2 
C)  H2S 
D)  H4S

Question 8

What element does not react with other elements?

Accepted Answer

A)  hydrogen 
B)  helium 
C)  oxygen 
D)  silicon 
A)  hydrogen 
B)  helium 
C)  oxygen 
D)  silicon

Question 9

In the following structure where A and B represent two different elements, the valency of A is ________ and B is ________.

Accepted Answer

A)  one; three 
B)  one; five 
C)  three; five 
D)  eight; eight 
A)  one; three 
B)  one; five 
C)  three; five 
D)  eight; eight

Question 10

We can represent atoms by listing the number of protons, neutrons, and electrons-for example, 2p+, 2n0, 2e- for helium. Which of the following represents the 18O isotope of oxygen?

Accepted Answer

A)  7p+, 2n0, 9e- 
B)  8p+, 10n0, 8e- 
C)  9p+, 9n0, 9e- 
D)  10p+, 8n0, 9e- 
A)  7p+, 2n0, 9e- 
B)  8p+, 10n0, 8e- 
C)  9p+, 9n0, 9e- 
D)  10p+, 8n0, 9e-

Question 11

Trace elements are those required by an organism in only minute quantities. Which of the following is a trace element that is required by all forms of life?

Accepted Answer

A)  arsenic 
B)  iodine 
C)  mercury 
D)  iron 
A)  arsenic 
B)  iodine 
C)  mercury 
D)  iron

Question 12

How many electrons are present in the +2 ionic form of the atom in the Periodic Table block shown in the figure?

Accepted Answer

A)  18 
B)  19 
C)  22 
D)  40 
A)  18 
B)  19 
C)  22 
D)  40

Question 13

What coefficients must be placed in the following blanks so that all atoms are accounted for in the products?
C6H12O6 → ________ C2H6O + ________ CO2

Accepted Answer

A)  2; 1 
B)  3; 1 
C)  1; 3 
D)  2; 2 
A)  2; 1 
B)  3; 1 
C)  1; 3 
D)  2; 2

Question 14

About 25 of the 92 natural elements are known to be essential to life. Four of these 25 elements make up approximately 96% of living matter. Which of the following elements account for most of the remaining 4% of an organism's mass?

Accepted Answer

A)  carbon, oxygen, hydrogen, nitrogen 
B)  calcium, potassium, phosphorus, sulfur 
C)  oxygen, hydrogen, calcium, nitrogen 
D)  carbon, hydrogen, nitrogen, oxygen 
A)  carbon, oxygen, hydrogen, nitrogen 
B)  calcium, potassium, phosphorus, sulfur 
C)  oxygen, hydrogen, calcium, nitrogen 
D)  carbon, hydrogen, nitrogen, oxygen

Question 15

An ion with six protons, seven neutrons, and a charge of 2+ has an atomic number of ________.

Accepted Answer

A)  four 
B)  five 
C)  six 
D)  seven 
A)  four 
B)  five 
C)  six 
D)  seven

Question 16

Which of the following statements is TRUE?

Accepted Answer

A)  Carbon, hydrogen, oxygen, and calcium are the most abundant elements of living matter. 
B)  Some naturally occurring elements are toxic to organisms. 
C)  All life requires the same essential elements. 
D)  A patient suffering from a goiter should not consume seafood. 
A)  Carbon, hydrogen, oxygen, and calcium are the most abundant elements of living matter. 
B)  Some naturally occurring elements are toxic to organisms. 
C)  All life requires the same essential elements. 
D)  A patient suffering from a goiter should not consume seafood.

Question 17

How many electrons are present in a H- and H+ ion respectively?

Accepted Answer

A)  1,2 
B)  2,1 
C)  2,0 
D)  0,2 
A)  1,2 
B)  2,1 
C)  2,0 
D)  0,2

Question 18

Which pair of elements is most likely to react if bought together?

Accepted Answer

A)  hydrogen and argon 
B)  sodium and chlorine 
C)  hydrogen and lithium 
D)  nitrogen and oxygen 
A)  hydrogen and argon 
B)  sodium and chlorine 
C)  hydrogen and lithium 
D)  nitrogen and oxygen

Question 19

Which of the following is true of oxygen that has 8 protons, 8 neutrons, and 8 electrons?

Accepted Answer

A)  It has a charge of +8. 
B)  It has a mass number of 8. 
C)  It has an atomic number of 8. 
D)  It has atomic number of 16. 
A)  It has a charge of +8. 
B)  It has a mass number of 8. 
C)  It has an atomic number of 8. 
D)  It has atomic number of 16.

Question 20

Which of the following types of representation would work best to indicate the type and number of atoms in a molecule?

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

Exam 2: Atoms and Molecules

Which of the following has the smallest total mass?

Compared with 31P, the radioactive isotop 32P has ________.

Van der Waals interactions may result under which of the following conditions?

Which statement is true of all atoms that are anions?

Nitrogen (N) is more electronegative than hydrogen (H). Which of the following is a correct statement about the atoms in ammonia (NH3)?

Under which of the following conditions will an atom be the most stable?

The atomic number of sulfur is 16. Sulfur combines with hydrogen by covalent bonding to form a compound, hydrogen sulfide. Based on the number of valence electrons in a sulfur atom, predict the molecular formula of the compound.

What element does not react with other elements?

In the following structure where A and B represent two different elements, the valency of A is ________ and B is ________.

We can represent atoms by listing the number of protons, neutrons, and electrons-for example, 2p+, 2n0, 2e- for helium. Which of the following represents the 18O isotope of oxygen?

Trace elements are those required by an organism in only minute quantities. Which of the following is a trace element that is required by all forms of life?

How many electrons are present in the +2 ionic form of the atom in the Periodic Table block shown in the figure?

What coefficients must be placed in the following blanks so that all atoms are accounted for in the products? C6H12O6 → ________ C2H6O + ________ CO2

About 25 of the 92 natural elements are known to be essential to life. Four of these 25 elements make up approximately 96% of living matter. Which of the following elements account for most of the remaining 4% of an organism's mass?

An ion with six protons, seven neutrons, and a charge of 2+ has an atomic number of ________.

Which of the following statements is TRUE?

How many electrons are present in a H- and H+ ion respectively?

Which pair of elements is most likely to react if bought together?

Which of the following is true of oxygen that has 8 protons, 8 neutrons, and 8 electrons?

Which of the following types of representation would work best to indicate the type and number of atoms in a molecule?

Biology and Its Themes

The Chemistry of Water

Carbon: the Basis of Molecular Diversity

Biological Macromolecules and Lipids

Energy and Life

Cell Structure and Function

Cell Membranes

Cellular Signaling

Cell Respiration

Photosynthetic Processes

Mitosis

Sexual Life Cycles and Meiosis

Mendelian Genetics

Linkage and Chromosomes

Nucleic Acids and Inheritance

Expression of Genes

Control of Gene Expression

Dna Technology

The Evolution of Genomes

How Evolution Works

Phylogenetic Reconstruction

Microevolution

Species and Speciation

Macroevolution

Introduction to Viruses

Prokaryotes

The Origin and Evolution of Eukaryotes

Nonvascular and Seedless Vascular Plants

Seed Plants

Introduction to Fungi

An Introduction to Animal Diversity

Invertebrates

Vertebrates

Plant Structure and Growth

Transport in Vascular Plants

Plant Nutrition

Reproduction of Flowering Plants

Plant Signals and Behavior

The Animal Body

Chemical Signals in Animals

Animal Digestive Systems

Animal Transport Systems

Animal Excretory Systems

Animal Reproductive Systems

Development in Animals

Animal Defenses Against Infection

Electrical Signals in Animals

Neural Regulation in Animals

Sensation and Movement in Animals

An Overview of Ecology

Behavioral Ecology

Populations and Life History Traits

Biodiversity and Communities

Energy Flow and Chemical Cycling in Ecosystems

Conservation and Global Ecology

Filters

In the following structure where A and B represent two different elements, the valency of A is and B is .

What coefficients must be placed in the following blanks so that all atoms are accounted for in the products? C6H12O₆ → C₂H₆O + CO₂