Question 1

Buffers are substances that help resist shifts in pH by

Accepted Answer

A)  releasing H+ to a solution when acids are added. 
B)  donating H+ to a solution when bases are added. 
C)  releasing OH- to a solution when bases are added. 
D)  accepting H+ from a solution when acids are added. 
E)  both donating H+ to a solution when bases are added and accepting H+ when acids are added. 
A)  releasing H+ to a solution when acids are added. 
B)  donating H+ to a solution when bases are added. 
C)  releasing OH- to a solution when bases are added. 
D)  accepting H+ from a solution when acids are added. 
E)  both donating H+ to a solution when bases are added and accepting H+ when acids are added.

Question 2

An atom has 6 electrons in its outer shell. How many unpaired electrons does it have?

Accepted Answer

A)  0 
B)  2 
C)  4 
D)  6 
E)  2 or 4 
A)  0 
B)  2 
C)  4 
D)  6 
E)  2 or 4

Question 3

Assume that acid rain has lowered the pH of a particular lake to pH 4.0. What is the hydroxyl ion concentration of this lake?

Accepted Answer

A)  1 × 10-10 mol of hydroxyl ion per liter of lake water 
B)  1 × 10-4 mol of hydroxyl ion per liter of lake water 
C)  10.0 M with regard to hydroxyl ion concentration 
D)  4.0 M with regard to hydroxyl ion concentration 
E)  1 × 10-4 mol of hydroxyl ion per liter of lake water and 4.0 M with regard to hydrogen ion concentration 
A)  1 × 10-10 mol of hydroxyl ion per liter of lake water 
B)  1 × 10-4 mol of hydroxyl ion per liter of lake water 
C)  10.0 M with regard to hydroxyl ion concentration 
D)  4.0 M with regard to hydroxyl ion concentration 
E)  1 × 10-4 mol of hydroxyl ion per liter of lake water and 4.0 M with regard to hydrogen ion concentration

Question 4

Carbon-12 is the most common isotope of carbon and has a mass number of 12. However, the atomic mass of carbon is slightly more than 12 daltons. Why?

Accepted Answer

A)  The atomic mass does not include the mass of electrons. 
B)  Some carbon atoms in nature have an extra proton. 
C)  Some carbon atoms in nature have more neutrons. 
D)  Some carbon atoms in nature have a different valence electron distribution. 
E)  Some carbon atoms in nature have undergone radioactive decay. 
A)  The atomic mass does not include the mass of electrons. 
B)  Some carbon atoms in nature have an extra proton. 
C)  Some carbon atoms in nature have more neutrons. 
D)  Some carbon atoms in nature have a different valence electron distribution. 
E)  Some carbon atoms in nature have undergone radioactive decay.

Question 5

When an ionic compound such as sodium chloride (NaCl) is placed in water, the component atoms of the NaCl crystal dissociate into individual sodium ions (Na+) and chloride ions (Cl-). In contrast, the atoms of covalently bonded molecules (e.g., glucose, sucrose, glycerol) do not generally dissociate when placed in aqueous solution. Which of the following solutions would be expected to contain the greatest number of solute particles (molecules or ions)?

Accepted Answer

A)  1 L of 0.5 M NaCl 
B)  1 L of 0.5 M glucose 
C)  1 L of 1.0 M NaCl 
D)  1 L of 1.0 M glucose 
E)  1 L of 1.0 M NaCl and 1 L of 1.0 M glucose will contain equal numbers of solute particles. 
A)  1 L of 0.5 M NaCl 
B)  1 L of 0.5 M glucose 
C)  1 L of 1.0 M NaCl 
D)  1 L of 1.0 M glucose 
E)  1 L of 1.0 M NaCl and 1 L of 1.0 M glucose will contain equal numbers of solute particles.

Question 6

Which type of bond must be broken for water to vaporize?

Accepted Answer

A)  ionic bonds 
B)  both hydrogen bonds and ionic bonds 
C)  polar covalent bonds 
D)  hydrogen bonds 
E)  both polar covalent bonds and hydrogen bonds 
A)  ionic bonds 
B)  both hydrogen bonds and ionic bonds 
C)  polar covalent bonds 
D)  hydrogen bonds 
E)  both polar covalent bonds and hydrogen bonds

Question 7

Figure 2.3
-Which drawing in Figure 2.3 depicts the electron configuration of an element with chemical properties most similar to those of helium (2He)?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E 
A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Question 8

Hydrophobic substances such as vegetable oil are

Accepted Answer

A)  nonpolar substances that repel water molecules. 
B)  nonpolar substances that have an attraction for water molecules. 
C)  polar substances that repel water molecules. 
D)  polar substances that have an affinity for water. 
E)  charged molecules that hydrogen-bond with water molecules. 
A)  nonpolar substances that repel water molecules. 
B)  nonpolar substances that have an attraction for water molecules. 
C)  polar substances that repel water molecules. 
D)  polar substances that have an affinity for water. 
E)  charged molecules that hydrogen-bond with water molecules.

Question 9

What is the hydrogen ion (H+) concentration of a solution of pH 8?

Accepted Answer

A)  8 M 
B)  8 × 10-6 M 
C)  0.01 M 
D)  10-8 M 
E)  10-6 M 
A)  8 M 
B)  8 × 10-6 M 
C)  0.01 M 
D)  10-8 M 
E)  10-6 M

Question 10

Water molecules are able to form hydrogen bonds with

Accepted Answer

A)  compounds that have polar covalent bonds. 
B)  oils. 
C)  oxygen gas (O2) molecules. 
D)  chloride ions. 
E)  any compound that is not soluble in water. 
A)  compounds that have polar covalent bonds. 
B)  oils. 
C)  oxygen gas (O2) molecules. 
D)  chloride ions. 
E)  any compound that is not soluble in water.

Question 11

In a single molecule of water, two hydrogen atoms are bonded to a single oxygen atom by

Accepted Answer

A)  hydrogen bonds. 
B)  nonpolar covalent bonds. 
C)  polar covalent bonds. 
D)  ionic bonds. 
E)  van der Waals interactions. 
A)  hydrogen bonds. 
B)  nonpolar covalent bonds. 
C)  polar covalent bonds. 
D)  ionic bonds. 
E)  van der Waals interactions.

Question 12

Knowing just the atomic mass of an element allows inferences about which of the following?

Accepted Answer

A)  the number of electrons in the element 
B)  the number of protons in the element 
C)  the number of neutrons in the element 
D)  the number of protons plus neutrons in the element 
E)  the number of protons plus electrons in the element 
A)  the number of electrons in the element 
B)  the number of protons in the element 
C)  the number of neutrons in the element 
D)  the number of protons plus neutrons in the element 
E)  the number of protons plus electrons in the element

Question 13

A slice of pizza has 500 kcal. If we could burn the pizza and use all the heat to warm a 50-L container of cold water, what would be the approximate increase in the temperature of the water? (Note: A liter of cold water weighs about 1 kg.)

Accepted Answer

A)  50°C 
B)  5°C 
C)  1°C 
D)  100°C 
E)  10°C 
A)  50°C 
B)  5°C 
C)  1°C 
D)  100°C 
E)  10°C

Question 14

Which of the following pairs of atoms would be most likely to form a polar covalent bond?

Accepted Answer

A) 
  
B) 
  
C) 
  
D) 
  
E) 
  
A) 
  
B) 
  
C) 
  
D) 
  
E)

Question 15

A small birthday candle is weighed. It is then lighted and placed beneath a metal can containing 100 mL of water. Careful records are kept as the temperature of the water rises. Data from this experiment are shown on the graph. What amount of heat energy is released in the burning of candle wax? (Note that 1 liter of pure water has a mass of 1 kg.)   Figure 2.11

Accepted Answer

A)  0.5 kilocalories per gram of wax burned 
B)  5 kilocalories per gram of wax burned 
C)  10 kilocalories per gram of wax burned 
D)  20 kilocalories per gram of wax burned 
E)  50 kilocalories per gram of wax burned 
A)  0.5 kilocalories per gram of wax burned 
B)  5 kilocalories per gram of wax burned 
C)  10 kilocalories per gram of wax burned 
D)  20 kilocalories per gram of wax burned 
E)  50 kilocalories per gram of wax burned

Question 16

What is the maximum number of hydrogen atoms that can be covalently bonded in a molecule containing two carbon atoms?

Accepted Answer

A)  2 
B)  3 
C)  4 
D)  6 
E)  8 
A)  2 
B)  3 
C)  4 
D)  6 
E)  8

Question 17

The nutritional information on a cereal box shows that one serving of a dry cereal has 200 kilocalories. If one were to burn one serving of the cereal, the amount of heat given off would be sufficient to raise the temperature of 20 kg of water how many degrees Celsius?

Accepted Answer

A)  0.2°C 
B)  1.0°C 
C)  2.0°C 
D)  10.0°C 
E)  20.0°C 
A)  0.2°C 
B)  1.0°C 
C)  2.0°C 
D)  10.0°C 
E)  20.0°C

Question 18

If a solution has a pH of 7, this means that

Accepted Answer

A)  there are no H+ ions in the water. 
B)  this is a solution of pure water. 
C)  the concentration of H+ ions in the water equals the concentration of OH- ions in the water. 
D)  this is a solution of pure water, and the concentration of H+ ions in the water is 10-7 M. 
E)  this is a solution of pure water, and the concentration of H+ ions equals the concentration of OH- ions in the water. 
A)  there are no H+ ions in the water. 
B)  this is a solution of pure water. 
C)  the concentration of H+ ions in the water equals the concentration of OH- ions in the water. 
D)  this is a solution of pure water, and the concentration of H+ ions in the water is 10-7 M. 
E)  this is a solution of pure water, and the concentration of H+ ions equals the concentration of OH- ions in the water.

Question 19

The atomic number of neon is 10. Therefore, which of the following is most correct about an atom of neon?

Accepted Answer

A)  It has 8 electrons in its outer electron shell. 
B)  It is inert. 
C)  It has an atomic mass of 10 daltons. 
D)  It has 8 electrons in its outer electron shell and it is inert. 
E)  It has 8 electrons in its outer electron shell, it is inert, and it has an atomic mass of 10 daltons. 
A)  It has 8 electrons in its outer electron shell. 
B)  It is inert. 
C)  It has an atomic mass of 10 daltons. 
D)  It has 8 electrons in its outer electron shell and it is inert. 
E)  It has 8 electrons in its outer electron shell, it is inert, and it has an atomic mass of 10 daltons.

Question 20

Research indicates that acid precipitation can damage certain marine organisms by

Accepted Answer

A)  buffering ocean waters. 
B)  decreasing the H+ concentration in oceans. 
C)  increasing the OH- concentration in oceans. 
D)  decreasing the concentration of carbonate ions in oceans. 
E)  both decreasing the H+ concentration and increasing the OH- concentration in oceans. 
A)  buffering ocean waters. 
B)  decreasing the H+ concentration in oceans. 
C)  increasing the OH- concentration in oceans. 
D)  decreasing the concentration of carbonate ions in oceans. 
E)  both decreasing the H+ concentration and increasing the OH- concentration in oceans.

Exam 2: The Chemical Context of Life

Buffers are substances that help resist shifts in pH by

An atom has 6 electrons in its outer shell. How many unpaired electrons does it have?

Assume that acid rain has lowered the pH of a particular lake to pH 4.0. What is the hydroxyl ion concentration of this lake?

Carbon-12 is the most common isotope of carbon and has a mass number of 12. However, the atomic mass of carbon is slightly more than 12 daltons. Why?

Which type of bond must be broken for water to vaporize?

Figure 2.3 -Which drawing in Figure 2.3 depicts the electron configuration of an element with chemical properties most similar to those of helium (2He)?

Hydrophobic substances such as vegetable oil are

What is the hydrogen ion (H+) concentration of a solution of pH 8?

Water molecules are able to form hydrogen bonds with

In a single molecule of water, two hydrogen atoms are bonded to a single oxygen atom by

Knowing just the atomic mass of an element allows inferences about which of the following?

A slice of pizza has 500 kcal. If we could burn the pizza and use all the heat to warm a 50-L container of cold water, what would be the approximate increase in the temperature of the water? (Note: A liter of cold water weighs about 1 kg.)

Which of the following pairs of atoms would be most likely to form a polar covalent bond?

What is the maximum number of hydrogen atoms that can be covalently bonded in a molecule containing two carbon atoms?

The nutritional information on a cereal box shows that one serving of a dry cereal has 200 kilocalories. If one were to burn one serving of the cereal, the amount of heat given off would be sufficient to raise the temperature of 20 kg of water how many degrees Celsius?

If a solution has a pH of 7, this means that

The atomic number of neon is 10. Therefore, which of the following is most correct about an atom of neon?

Research indicates that acid precipitation can damage certain marine organisms by

Introduction: Evolution and the Foundations of Biology

Carbon and the Molecular Diversity of Life

A Tour of the Cell

Membrane Transport and Cell Signaling

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

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

Development, Stem Cells, and Cancer

Viruses

Genomes and Their Evolution

Descent With Modification

Phylogeny

The Evolution of Populations

The Origin of Species

Broad Patterns of Evolution

Early Life and the Diversification of Prokaryotes

The Origin and Diversification of Eukaryotes

The Colonization of Land by Plants and Fungi

The Rise of Animal Diversity

Plant Structure and Growth

Resource Acquisition, Nutrition, and Transport in Vascular Plants

Reproduction and Domestication of Flowering Plants

Plant Responses to Internal and External Signals

Homeostasis and Endocrine Signaling

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Reproduction and Development

Neurons, Synapses, and Signaling

Nervous and Sensory Systems

Motor Mechanisms and Behavior

Population Ecology and the Distribution of Organisms

Species Interactions

Ecosystems and Energy

Global Ecology and Conservation Biology

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