Question 1

A molecule with the general formula CH₂O is a(n)

Accepted Answer

A) protein. 
B) carbohydrate. 
C) amino acid. 
D) nucleic acid.

Question 2

Most lipids contain one or more of the long, hydrophobic hydrocarbon chains known as ____________________.

Accepted Answer

The answer of Most lipids contain one or more of...

Question 3

Nucleic acids contain phosphorus but not sulfur.

Accepted Answer

A) True 
 B)False

Question 4

We use soap to clean ourselves better than we could with water alone. Soaps contain phospholipids that are responsible for the cleansing action. Which of the following statements is the most likely explanation for how soaps work?

Accepted Answer

A) Phospholipids are ions and therefore mix with both the water and oily dirt. 
B) Phospholipids are completely hydrophilic, and therefore oily dirt takes the place of the phospholipid molecules that would be dissolved in the rinse water. 
C) The phospholipid tail attaches to the oily dirt while the phospholipid head interacts with the rinse water and carries the dirt (and soap) away with it. 
D) The nonpolar fatty acid chains that make up the heads of the phospholipid are hydrophilic, and thus are repelled by the water.

Question 5

An atom of the element with the atomic number of 11 (which can form an ion)always contains 11 _____.

Accepted Answer

A) neutrons 
B) nuclei 
C) electrons 
D) protons

Question 6

In the equation, 2 H₂O₂ → 2 H₂O + O₂, the H₂O₂ molecules are the _____ and the H₂O + O₂ molecules are the _____.

Accepted Answer

A) products; products 
B) reactants; products 
C) products; reactants 
D) reactants; reactants

Question 7

After adding a small amount of Solution A to Solution B, the pH of Solution B declines from 8 to 3. Solution A must contain

Accepted Answer

A) a salt. 
B) an acid. 
C) water only. 
D) a base.

Question 8

Because both the wood in a tree branch and the spider's exoskeleton are composed of
low-density cellulose each floats when placed in water.

Accepted Answer

A) True 
 B)False

Question 9

____________________ are the most hydrophobic of the four classes of organic compounds because they are made of hydrocarbon chains that repel water.

Accepted Answer

The answer of ____________________ are the most hydrophobic of the...

Question 10

Chemists often represent the structure of atoms using p, n, and e to indicate the numbers of protons, neutrons, and electrons; which atom would have an atomic weight of 30?

Accepted Answer

A) 10 p, 10 n, 10 e 
B) 15 p, 15 n, 15 e 
C) 15 p, 0 n, 15 e 
D) 0 p, 15 n, 15 e

Question 11

Lipids with a four-ring structure are called ____________________.

Accepted Answer

The answer of Lipids with a four-ring structure are called...

Question 12

The primary structure of a protein consists of its amino acid sequence.

Accepted Answer

A) True 
 B)False

Question 13

The carbon dioxide you breathe out is carried to the lungs in the blood. Carbon dioxide, when dissolved in water, is an acid. How does the body prevent your blood from becoming too acidic on the way to your lungs?

Accepted Answer

A) Buffers in the blood release OH- ions to make the blood more basic. 
B) Buffers in the blood accept H+ ions to make the blood less acidic. 
C) Buffers in the blood release H+ to make the blood more basic. 
D) Buffers in the blood accept OH- to make the blood less acidic.

Question 14

The figure below shows the structural and space-filling models for stearic acid and oleic acid. 
Although the two fatty acids have the same number of carbon atoms, they have different three-dimensional configurations; oleic acid has a slight bend near the middle. As a result,

Accepted Answer

A) a pure sample of oleic acid would be more liquid than a pure sample of stearic acid. 
B) stearic acid would be classified as an unsaturated fatty acid. 
C) you would be more likely to find stearic acid in the form of an oil than in the form of a fat. 
D) oleic acid would be classified a saturated fatty acid.

Question 15

Oxygen has six electrons in its outer shell that can hold up to eight electrons. As a result, oxygen will commonly form ____________________ covalent bonds.

Accepted Answer

The answer of Oxygen has six electrons in its outer...

Question 16

____________________ molecules are nonpolar molecules that are repelled by water.

Accepted Answer

The answer of ____________________ molecules are nonpolar molecules that are...

Question 17

Covalent bonds contain ions.

Accepted Answer

A) True 
 B)False

Question 18

An acid is a polar substance that dissolves in water and

Accepted Answer

A) becomes nonpolar. 
B) leaves behind an OH- ion. 
C) accepts hydrogen ions from the solution. 
D) donates hydrogen ions to the solution.

Question 19

An atom is in its most stable state when all its electron shells are filled to capacity.

Accepted Answer

A) True 
 B)False

Question 20

An atom that becomes charged due to the gain or loss of an electron is called a(n)____________________.

Accepted Answer

The answer of An atom that becomes charged due to...

Exam 5: The Chemistry of Life

A molecule with the general formula CH₂O is a(n)

Most lipids contain one or more of the long, hydrophobic hydrocarbon chains known as ____________________.

Nucleic acids contain phosphorus but not sulfur.

We use soap to clean ourselves better than we could with water alone. Soaps contain phospholipids that are responsible for the cleansing action. Which of the following statements is the most likely explanation for how soaps work?

An atom of the element with the atomic number of 11 (which can form an ion) always contains 11 _____.

In the equation, 2 H₂O₂ → 2 H₂O + O₂, the H₂O₂ molecules are the _ and the H₂O + O₂ molecules are the _.

After adding a small amount of Solution A to Solution B, the pH of Solution B declines from 8 to 3. Solution A must contain

Because both the wood in a tree branch and the spider's exoskeleton are composed of low-density cellulose each floats when placed in water.

____________________ are the most hydrophobic of the four classes of organic compounds because they are made of hydrocarbon chains that repel water.

Chemists often represent the structure of atoms using p, n, and e to indicate the numbers of protons, neutrons, and electrons; which atom would have an atomic weight of 30?

Lipids with a four-ring structure are called ____________________.

The primary structure of a protein consists of its amino acid sequence.

The carbon dioxide you breathe out is carried to the lungs in the blood. Carbon dioxide, when dissolved in water, is an acid. How does the body prevent your blood from becoming too acidic on the way to your lungs?

The figure below shows the structural and space-filling models for stearic acid and oleic acid. Although the two fatty acids have the same number of carbon atoms, they have different three-dimensional configurations; oleic acid has a slight bend near the middle. As a result,

Oxygen has six electrons in its outer shell that can hold up to eight electrons. As a result, oxygen will commonly form ____________________ covalent bonds.

____________________ molecules are nonpolar molecules that are repelled by water.

Covalent bonds contain ions.

An acid is a polar substance that dissolves in water and

An atom is in its most stable state when all its electron shells are filled to capacity.

An atom that becomes charged due to the gain or loss of an electron is called a(n)____________________.