Question 1

Radioactive isotopes

Accepted Answer

A)  are frequently added to foods as nutritional supplements. 
B)  can be used in conjunction with PET scans to diagnose diseases. 
C)  do not occur naturally. 
D)  are never incorporated into organic compounds. 
A)  are frequently added to foods as nutritional supplements. 
B)  can be used in conjunction with PET scans to diagnose diseases. 
C)  do not occur naturally. 
D)  are never incorporated into organic compounds. B

Question 2

Glycolysis is the first step of cellular respiration, in which glucose is used to generate ATP to power the cell. The major chemical reaction that takes place in glycolysis (ignoring some other reactants and products) is the conversion of glucose (C6H12O6) to pyruvate (C3H4O3) and hydrogen ions (H+). Using this information, what is the correct equation for the glycolysis chemical reaction?

Accepted Answer

A)  C6H12O6 → C3H4O3 + H+ 
B)  C6H12O6 → 2 C3H4O3 + 2 H+ 
C)  C6H12O6 → 2 C3H4O3 + H+ 
D)  2 C6H12O6 → C3H4O3 + 2 H+ 
A)  C6H12O6 → C3H4O3 + H+ 
B)  C6H12O6 → 2 C3H4O3 + 2 H+ 
C)  C6H12O6 → 2 C3H4O3 + H+ 
D)  2 C6H12O6 → C3H4O3 + 2 H+ B

Question 3

Electrons move about the nucleus of an atom in the same way that

Accepted Answer

A)  insects fly around a bright lamp at night. 
B)  cars are parked along the sides of a street. 
C)  boats cross a lake. 
D)  birds migrate to a new winter home. 
A)  insects fly around a bright lamp at night. 
B)  cars are parked along the sides of a street. 
C)  boats cross a lake. 
D)  birds migrate to a new winter home. A

Question 4

Thin-layer chromatography is a method that can be used to separate molecules by their polarity. A mixture of molecules in a nonpolar liquid (the mobile phase) is added to the bottom of a piece of adsorbent material (the stationary phase) and allowed to migrate up the material. More-polar molecules interact more strongly with the stationary phase and thus migrate less. Less-polar molecules interact less strongly with the stationary phase and thus migrate more. Below are sample data for four different molecules from a thin-layer chromatography experiment. [Art: custom PowerPoint figure created by the author]
-Below are the structures of two molecules: ethanol and cyclohexane. Which would migrate farther in a thin-layer chromatography experiment? [Art: modified from Wikipedia images of the structures]

Accepted Answer

A)  Cyclohexane would migrate farther. 
B)  Ethanol would migrate farther. 
C)  Cyclohexane and ethanol would migrate equal distances. 
A)  Cyclohexane would migrate farther. 
B)  Ethanol would migrate farther. 
C)  Cyclohexane and ethanol would migrate equal distances.

Question 5

The sodium atom contains 11 electrons, 11 protons, and 12 neutrons. What is the mass number of sodium?

Accepted Answer

A)  11 
B)  22 
C)  23 
D)  34 
A)  11 
B)  22 
C)  23 
D)  34

Question 6

A diabetic, who does not utilize insulin properly, will metabolize fats instead of glucose. A condition called diabetic ketoacidosis is a common result of excessive fat metabolism, causing blood pH values of 7.1 or less (normal range is 7.35-7.45). What has happened to the blood pH and why?

Accepted Answer

A)  The pH is above normal (basic) because the ketones are too basic. 
B)  The pH is below normal (acidic) because the buffering capacity was exceeded. 
C)  The pH is not affected because the blood buffers can absorb the excess H+. 
D)  The pH is below normal because buffers can donate OH+. 
A)  The pH is above normal (basic) because the ketones are too basic. 
B)  The pH is below normal (acidic) because the buffering capacity was exceeded. 
C)  The pH is not affected because the blood buffers can absorb the excess H+. 
D)  The pH is below normal because buffers can donate OH+.

Question 7

The figure below shows five water molecules. The hydrogen bonds shown in this figure are each between

Accepted Answer

A)  two hydrogen atoms. 
B)  an oxygen and a hydrogen atom of the same water molecule. 
C)  an oxygen and a hydrogen atom of different water molecules. 
D)  two atoms with the same charge. 
A)  two hydrogen atoms. 
B)  an oxygen and a hydrogen atom of the same water molecule. 
C)  an oxygen and a hydrogen atom of different water molecules. 
D)  two atoms with the same charge.

Question 8

The body uses atoms in different ways to accomplish different tasks. For example, one portion of the body's calcium supply strengthens bones, whereas another portion combines with proteins to stimulate blood clotting after tissue injury. Which of the following statements provides the most logical chemical explanation of calcium's ability to perform such different functions?

Accepted Answer

A)  The bone contains calcium salts, which are less reactive than the calcium ions found in the blood. 
B)  The calcium in blood is a more reactive form of the atom and therefore has fewer protons than the calcium in bone. 
C)  There are many different isotopes of calcium, and the most reactive isotope is found in the bone. 
D)  The calcium in blood has a lighter atomic mass than the calcium in bone and is in a more reactive form. 
A)  The bone contains calcium salts, which are less reactive than the calcium ions found in the blood. 
B)  The calcium in blood is a more reactive form of the atom and therefore has fewer protons than the calcium in bone. 
C)  There are many different isotopes of calcium, and the most reactive isotope is found in the bone. 
D)  The calcium in blood has a lighter atomic mass than the calcium in bone and is in a more reactive form.

Question 9

You hypothesize that a tablet of PEPCID AC can neutralize more stomach acid than a tablet of Alka-Seltzer. If you placed a tablet of each antacid in a beaker of acid at an initial pH of 2, which of the following experimental results would support your hypothesis?

Accepted Answer

A)  After 1 hour, the pH of the solution in the PEPCID AC beaker was 9.2 and the pH of the solution in the Alka-Seltzer beaker was 8.3. 
B)  After 1 hour, the pH of the solution in the PEPCID AC beaker was 7.9 and the pH of the solution in the Alka-Seltzer beaker was 9.6. 
C)  After 1 hour, the pH of the solution in the PEPCID AC beaker was equal to that of the pH of the solution in the Alka-Seltzer beaker. 
D)  It took 3 minutes for the PEPCID AC tablet to fully dissolve, and it took 5 minutes for the Alka-Seltzer tablet to fully dissolve. 
A)  After 1 hour, the pH of the solution in the PEPCID AC beaker was 9.2 and the pH of the solution in the Alka-Seltzer beaker was 8.3. 
B)  After 1 hour, the pH of the solution in the PEPCID AC beaker was 7.9 and the pH of the solution in the Alka-Seltzer beaker was 9.6. 
C)  After 1 hour, the pH of the solution in the PEPCID AC beaker was equal to that of the pH of the solution in the Alka-Seltzer beaker. 
D)  It took 3 minutes for the PEPCID AC tablet to fully dissolve, and it took 5 minutes for the Alka-Seltzer tablet to fully dissolve.

Question 10

In the equation 2 H2 + O2 → 2 H2O, the H2 molecules are ________ and the H2O molecules are ________.

Accepted Answer

A)  reactants; products 
B)  products; reactants 
C)  created; destroyed 
D)  used; stored 
A)  reactants; products 
B)  products; reactants 
C)  created; destroyed 
D)  used; stored

Question 11

An uncharged atom of boron has an atomic number of 5 and an atomic mass of 11. How many electrons does boron have?

Accepted Answer

A)  11 
B)  15 
C)  5 
D)  2 
A)  11 
B)  15 
C)  5 
D)  2

Question 12

Uranium is a metallic element that is used in nuclear reactors and nuclear weapons. The vast majority of uranium found on Earth is in the form of uranium-238, an isotope with a mass number of 238, while the uranium that is used for nuclear reactors and weapons is uranium-235, an isotope with a mass number of 235.
-If the atomic mass of uranium is 92, how many neutrons does an atom of uranium-235 have in its nucleus?

Accepted Answer

A)  92 
B)  143 
C)  146 
D)  235 
A)  92 
B)  143 
C)  146 
D)  235

Question 13

A buffer

Accepted Answer

A)  is an acid that is used to offset overly basic conditions in the body. 
B)  is a base that is used to offset overly acidic conditions in the body. 
C)  donates H+ ions when conditions become too basic and accepts H+ ions when conditions become too acidic. 
D)  donates OH- ions when conditions become too basic and accepts OH- ions when conditions become too acidic. 
A)  is an acid that is used to offset overly basic conditions in the body. 
B)  is a base that is used to offset overly acidic conditions in the body. 
C)  donates H+ ions when conditions become too basic and accepts H+ ions when conditions become too acidic. 
D)  donates OH- ions when conditions become too basic and accepts OH- ions when conditions become too acidic.

Question 14

The hydrogen atoms of a water molecule are bonded to the oxygen atom by ________ bonds, whereas neighboring water molecules are held together by ________ bonds.

Accepted Answer

A)  hydrogen; polar covalent 
B)  polar covalent; hydrogen 
C)  ionic; covalent 
D)  polar covalent; ionic 
A)  hydrogen; polar covalent 
B)  polar covalent; hydrogen 
C)  ionic; covalent 
D)  polar covalent; ionic

Question 15

You've been experiencing acid indigestion lately, and you'd like a quick fix for the problem. You do a little research on the Internet and discover that your problem is caused by excess stomach acid. In the pharmacy aisles, however, you're having a little trouble deciding what to purchase to address the problem. At the pharmacy counter, the clerk recommends that you purchase PEPCID AC or Alka-Seltzer tablets.
-If you could check the pH of the recommended tablets, you would expect it to be

Accepted Answer

A)  higher than 7. 
B)  lower than 7. 
C)  exactly 7. 
D)  pH neutral. 
A)  higher than 7. 
B)  lower than 7. 
C)  exactly 7. 
D)  pH neutral.

Question 16

In a water molecule, hydrogen and oxygen are held together by a ________ bond.

Accepted Answer

A)  double covalent 
B)  nonpolar covalent 
C)  hydrogen 
D)  polar covalent 
A)  double covalent 
B)  nonpolar covalent 
C)  hydrogen 
D)  polar covalent

Question 17

Below is the structure of octane, the major component of gasoline. What type(s) of bond(s) is(are) found in a molecule of octane?

Accepted Answer

A)  only nonpolar covalent bonds 
B)  only polar covalent bonds 
C)  hydrogen bonds and polar covalent bonds 
D)  ionic bonds and nonpolar covalent bonds 
A)  only nonpolar covalent bonds 
B)  only polar covalent bonds 
C)  hydrogen bonds and polar covalent bonds 
D)  ionic bonds and nonpolar covalent bonds

Question 18

Compared to a solution of pH 3, a solution of pH 1 is

Accepted Answer

A)  100 times more acidic. 
B)  10 times more acidic. 
C)  10 times more basic. 
D)  100 times more basic. 
A)  100 times more acidic. 
B)  10 times more acidic. 
C)  10 times more basic. 
D)  100 times more basic.

Question 19

In the equation 2 H2 + O2 → 2 H2O,

Accepted Answer

A)  H2, O2, and H2O are all compounds. 
B)  H2, O2, and H2O are all elements. 
C)  only H2O is a compound. 
D)  only H2 and O2 are compounds. 
A)  H2, O2, and H2O are all compounds. 
B)  H2, O2, and H2O are all elements. 
C)  only H2O is a compound. 
D)  only H2 and O2 are compounds.

Question 20

A radioactive isotope is an isotope that

Accepted Answer

A)  is stable. 
B)  decays. 
C)  has more protons than the common variant of the element. 
D)  has the same atomic mass but a different atomic number than the common variant of the element. 
A)  is stable. 
B)  decays. 
C)  has more protons than the common variant of the element. 
D)  has the same atomic mass but a different atomic number than the common variant of the element.

Exam 2: The Chemical Basis of Life

Radioactive isotopes

Electrons move about the nucleus of an atom in the same way that

The sodium atom contains 11 electrons, 11 protons, and 12 neutrons. What is the mass number of sodium?

A diabetic, who does not utilize insulin properly, will metabolize fats instead of glucose. A condition called diabetic ketoacidosis is a common result of excessive fat metabolism, causing blood pH values of 7.1 or less (normal range is 7.35-7.45). What has happened to the blood pH and why?

The figure below shows five water molecules. The hydrogen bonds shown in this figure are each between

You hypothesize that a tablet of PEPCID AC can neutralize more stomach acid than a tablet of Alka-Seltzer. If you placed a tablet of each antacid in a beaker of acid at an initial pH of 2, which of the following experimental results would support your hypothesis?

In the equation 2 H2 + O2 → 2 H2O, the H2 molecules are ________ and the H2O molecules are ________.

An uncharged atom of boron has an atomic number of 5 and an atomic mass of 11. How many electrons does boron have?

A buffer

The hydrogen atoms of a water molecule are bonded to the oxygen atom by ________ bonds, whereas neighboring water molecules are held together by ________ bonds.

In a water molecule, hydrogen and oxygen are held together by a ________ bond.

Below is the structure of octane, the major component of gasoline. What type(s) of bond(s) is(are) found in a molecule of octane?

Compared to a solution of pH 3, a solution of pH 1 is

In the equation 2 H2 + O2 → 2 H2O,

A radioactive isotope is an isotope that

Biology: Exploring Life

The Molecules of Cells

A Tour of the Cell

The Working Cell

How Cells Harvest Chemical Energy

Photosynthesis: Using Light to Make Food

The Cellular Basis of Reproduction and Inheritance

Patterns of Inheritance

Molecular Biology of the Gene

How Genes Are Controlled

DNA Technology and Genomics

How Populations Evolve

The Origin of Species

Tracing Evolutionary History

Microbial Life: Prokaryotes and Protists

The Evolution of Plant and Fungal Diversity

The Evolution of Invertebrate Diversity

The Evolution of Vertebrate Diversity

Unifying Concepts of Animal Structure and Function

Nutrition and Digestion

Gas Exchange

Circulation

The Immune System

Control of Body Temperature and Water Balance

Hormones and the Endocrine System

Reproduction and Embryonic Development

Nervous Systems

The Senses

How Animals Move

Plant Structure, Growth, and Reproduction

Plant Nutrition and Transport

Control Systems in Plants

The Biosphere: an Introduction to Earths Diverse Environments

Behavioral Adaptations to the Environment

Population Ecology

Communities and Ecosystems

Conservation Biology

Filters

In the equation 2 H₂ + O₂ → 2 H₂O, the H₂ molecules are and the H₂O molecules are .

The hydrogen atoms of a water molecule are bonded to the oxygen atom by bonds, whereas neighboring water molecules are held together by bonds.

In the equation 2 H₂ + O₂ → 2 H₂O,