Question 1

As the pH increases, the hydroxide ion concentration ________.

Accepted Answer

A) goes down 
B) gets larger 
C) starts to affect the H+ concentration 
D) starts to decrease because it is reacting with the excess hydronium ions 
E) stays constant 
A) goes down 
B) gets larger 
C) starts to affect the H+ concentration 
D) starts to decrease because it is reacting with the excess hydronium ions 
E) stays constant B

Question 2

Why do we use the pH scale to indicate the acidity of a solution rather than simply stating the concentration of hydronium ions?

Accepted Answer

A) It includes the concentration of hydronium and hydroxide ions. 
B) It is used because the general public understands it. 
C) It is more accurate to use the pH scale. 
D) It is more convenient, since the concentration of hydronium ions is so small. 
A) It includes the concentration of hydronium and hydroxide ions. 
B) It is used because the general public understands it. 
C) It is more accurate to use the pH scale. 
D) It is more convenient, since the concentration of hydronium ions is so small. D

Question 3

What would be the concentration of hydronium ions in a solution that had a pH = -3? Why would such a solution be impossible to prepare?

Accepted Answer

A) Concentration of     = 3 M. It is impossible because it is hard to measure such a small amount of hydronium ions accurately. 
B) Concentration of     = 30 M. It is impossible because pH can not be negative. 
C) Concentration of     =   M. It is impossible because any container used to hold the acid would immediately corrode. 
D) Concentration of     =   M. It is impossible because only so much acid can dissolve in water before the solution becomes saturated. 
A) Concentration of     = 3 M. It is impossible because it is hard to measure such a small amount of hydronium ions accurately. 
B) Concentration of     = 30 M. It is impossible because pH can not be negative. 
C) Concentration of     =   M. It is impossible because any container used to hold the acid would immediately corrode. 
D) Concentration of     =   M. It is impossible because only so much acid can dissolve in water before the solution becomes saturated. D

Question 4

Which of the following statements describes a neutral solution?

Accepted Answer

A) [H3O+] > [OH-] 
B) [H3O+] -] 
C) [H3O+] × [OH-] ≠ 1 × 10-14 
D) [H3O+]/[OH-] = 1 × 10-14 
E) [H3O+]/[OH-] = 1 
A) [H3O+] > [OH-] 
B) [H3O+] -] 
C) [H3O+] × [OH-] ≠ 1 × 10-14 
D) [H3O+]/[OH-] = 1 × 10-14 
E) [H3O+]/[OH-] = 1

Question 5

For the following acid-base reaction, identify what is formed in the space marked. H2SO4 + KOH ⇌ KHSO4 + ???

Accepted Answer

A) K2SO4 
B) H3OSO4 
C) H2O 
D) KOH2SO4 
E) none of the above 
A) K2SO4 
B) H3OSO4 
C) H2O 
D) KOH2SO4 
E) none of the above

Question 6

For the following acid-base reaction, identify what is formed in the space marked. HF + KOH ⇌ ???? + H2O

Accepted Answer

A) KF 
B) H3OF 
C) KOH2 
D) KOH2F 
E) none of the above 
A) KF 
B) H3OF 
C) KOH2 
D) KOH2F 
E) none of the above

Question 7

What is the source of acid rain?

Accepted Answer

A) Acid rain is from dissolved carbon dioxide. 
B) All rain is acid rain because rain has a pH is less than 7. 
C) Rain is normally basic, but depending on the weather it can get slightly acidic. 
D) All rain is acid rain because rain has a hydronium ion concentration greater than 10-7 M. 
E) none of the above 
A) Acid rain is from dissolved carbon dioxide. 
B) All rain is acid rain because rain has a pH is less than 7. 
C) Rain is normally basic, but depending on the weather it can get slightly acidic. 
D) All rain is acid rain because rain has a hydronium ion concentration greater than 10-7 M. 
E) none of the above

Question 8

According to the following reaction, which molecule is acting as a base? H2O + NH3 → OH- + NH4+

Accepted Answer

A) H2O 
B) NH3 
C) OH- 
D) NH4+ 
E) none of the above 
A) H2O 
B) NH3 
C) OH- 
D) NH4+ 
E) none of the above

Question 9

According to the following reaction, which molecule is acting as an acid? H3O+ + HSO4- → H2O + H2SO4

Accepted Answer

A) H2SO4 
B) H2O 
C) H3O+ 
D) HSO4- 
E) none of the above 
A) H2SO4 
B) H2O 
C) H3O+ 
D) HSO4- 
E) none of the above

Question 10

In the following buffer system, what happens to the concentration of the highlighted molecule if you add acid in the form of H3O+? HF + NaF + H2O ⇌ F- + H3O+ + Na+

Accepted Answer

A) increases 
B) decreases 
C) stays about the same 
D) Buffers do not change. 
E) none of the above 
A) increases 
B) decreases 
C) stays about the same 
D) Buffers do not change. 
E) none of the above

Question 11

The amphoteric reaction between two water molecules is endothermic, which means that this reaction requires the input of energy in order to proceed: Energy +   O +   O →     + O   The warmer the temperature of the water, the more thermal energy is available for this reaction, and the more hydronium and hydroxide ions are formed. Based on this information, should the value of   be expected to increase, decrease, or stay the same with increasing temperature?

Accepted Answer

A) The value of   will stay the same, since it is a constant. 
B) The value of   will decrease, since there are more hydronium ions than hydroxide ions. 
C) The value of   will increase since the rise in temperature allows for a higher concentration of both ions. 
D) The value of   will decrease since there are more hydroxide ions than hydronium ions. 
A) The value of   will stay the same, since it is a constant. 
B) The value of   will decrease, since there are more hydronium ions than hydroxide ions. 
C) The value of   will increase since the rise in temperature allows for a higher concentration of both ions. 
D) The value of   will decrease since there are more hydroxide ions than hydronium ions.

Question 12

Would it be easier or harder for a water molecule to donate a hydrogen ion if its polar H-O bond were even more polar? Why?

Accepted Answer

A) Easier. As polarity increases the bond classification tends towards ionic. An ionic bond would mean a greater separation of positive and negative charge making it easier for the water molecule to donate a hydrogen ion. 
B) Harder. Increasing the polarity makes the bond stronger. The stronger the bond the more difficult it would be for the water molecule to donate a hydrogen ion. 
C) Neither. Increasing the polarity of the O-H bond would not affect the hydrogen bonding between the water molecules and therefore have no effect on the water molecule's ability to donate a hydrogen ion. 
D) Both. The ability of the water molecule to donate a hydrogen ion is dependent upon the environment you place it in. If the surrounding molecules are more covalent, donating the electron would be harder. However, if water found itself in a highly polar environment, increasing the O-H polarity would make it easier. 
A) Easier. As polarity increases the bond classification tends towards ionic. An ionic bond would mean a greater separation of positive and negative charge making it easier for the water molecule to donate a hydrogen ion. 
B) Harder. Increasing the polarity makes the bond stronger. The stronger the bond the more difficult it would be for the water molecule to donate a hydrogen ion. 
C) Neither. Increasing the polarity of the O-H bond would not affect the hydrogen bonding between the water molecules and therefore have no effect on the water molecule's ability to donate a hydrogen ion. 
D) Both. The ability of the water molecule to donate a hydrogen ion is dependent upon the environment you place it in. If the surrounding molecules are more covalent, donating the electron would be harder. However, if water found itself in a highly polar environment, increasing the O-H polarity would make it easier.

Question 13

What results when water,   O, reacts with sulfur dioxide, S   ?

Accepted Answer

A)    O + S   →    (aq) 
B) 2   O + 2 S   → 2      (aq)+   (g) 
C)    O + S   → S   (g)+   (g) 
D)    O + S   → No Reaction 
A)    O + S   →    (aq) 
B) 2   O + 2 S   → 2      (aq)+   (g) 
C)    O + S   → S   (g)+   (g) 
D)    O + S   → No Reaction

Question 14

What would be the best explanation for the fact that most natural water has a pH of about 5.6?

Accepted Answer

A) Carbon dioxide reacts with water to form an acid. 
B) Air contains acid rain particles. 
C) Minerals that are dissolved in water are often acidic. 
D) Many salts that dissolve in natural waters make the water basic. 
E) none of the above 
A) Carbon dioxide reacts with water to form an acid. 
B) Air contains acid rain particles. 
C) Minerals that are dissolved in water are often acidic. 
D) Many salts that dissolve in natural waters make the water basic. 
E) none of the above

Question 15

Sometimes an individual going through a traumatic experience cannot stop hyperventilating. In such a circumstance, it is recommended that the individual breath into a paper bag or cupped hands as a useful way to avoid an increase in blood pH, which can cause the person to pass out. Explain how this works.

Accepted Answer

A) Carbon dioxide initially exhaled is reinhaled to help maintain adequate levels of carbonic acid in the blood. 
B) It helps to slow their breathing down to prevent excess oxygen from entering the blood. 
C) The paper absorbs C   to prevent the accumulation of excess C   in the blood. 
D) The paper bag helps to retain the water vapor leaving the mouth to prevent an increase in the concentration of lactic acid in the body. 
A) Carbon dioxide initially exhaled is reinhaled to help maintain adequate levels of carbonic acid in the blood. 
B) It helps to slow their breathing down to prevent excess oxygen from entering the blood. 
C) The paper absorbs C   to prevent the accumulation of excess C   in the blood. 
D) The paper bag helps to retain the water vapor leaving the mouth to prevent an increase in the concentration of lactic acid in the body.

Question 16

A weak acid is added to a concentrated solution of hydrochloric acid. Does the solution become more or less acidic?

Accepted Answer

A) More acidic, since there are more hydronium ions being added to the solution. 
B) Less acidic, since the solution becomes more dilute with a less concentrated solution of hydronium ions being added to the solution. 
C) No change in acidity, since the concentration of the hydrochloric acid is too high to be changed by the weak solution. 
D) Less acidic since the concentration of hydroxide ions will increase. 
A) More acidic, since there are more hydronium ions being added to the solution. 
B) Less acidic, since the solution becomes more dilute with a less concentrated solution of hydronium ions being added to the solution. 
C) No change in acidity, since the concentration of the hydrochloric acid is too high to be changed by the weak solution. 
D) Less acidic since the concentration of hydroxide ions will increase.

Question 17

Which of the following statements about strong and weak bases is not true?

Accepted Answer

A) A weak base does not completely dissociate in water. 
B) A weak base will not react with a strong acid. 
C) A strong base can be extremely corrosive. 
D) A strong base will readily accept protons from even weak acids. 
E) All of the above are untrue. 
A) A weak base does not completely dissociate in water. 
B) A weak base will not react with a strong acid. 
C) A strong base can be extremely corrosive. 
D) A strong base will readily accept protons from even weak acids. 
E) All of the above are untrue.

Question 18

Why is phosphoric acid,     , a stronger acid than disodium hydrogen phosphate,   ?

Accepted Answer

A) Phosphoric acid has three acidic hydrogens which makes it three times as acidic. 
B) Some of the released sodium ions in   HP   form NaOH (a base), which decreases the acidity of the   HP   . 
C) Phosphoric acid dissociates 100% in water whereas   HP   only dissociates about 50%. 
D) None of the above accurately describes why phosphoric acid is a stronger acid than disodium hydrogen phosphate. 
A) Phosphoric acid has three acidic hydrogens which makes it three times as acidic. 
B) Some of the released sodium ions in   HP   form NaOH (a base), which decreases the acidity of the   HP   . 
C) Phosphoric acid dissociates 100% in water whereas   HP   only dissociates about 50%. 
D) None of the above accurately describes why phosphoric acid is a stronger acid than disodium hydrogen phosphate.

Question 19

Cutting back on the pollutants that cause acid rain is one solution to the problem of acidified lakes. Suggest another.

Accepted Answer

A) stop using NaCl to salt the roads in the winter 
B) add a neutralizing substance such as limestone 
C) add ammonium ions to the lakes 
D) add chlorine and filter the water to remove any acidity in the lake 
A) stop using NaCl to salt the roads in the winter 
B) add a neutralizing substance such as limestone 
C) add ammonium ions to the lakes 
D) add chlorine and filter the water to remove any acidity in the lake

Question 20

Which of the following statements describes an acidic solution?

Accepted Answer

A) [H3O+] > [OH-] 
B) [H3O+] -] 
C) [H3O+] × [OH-] ≠ 1 × 10-14 
D) [H3O+]/[OH-] = 1 × 10-14 
E) [H3O+]/[OH-] = 1 
A) [H3O+] > [OH-] 
B) [H3O+] -] 
C) [H3O+] × [OH-] ≠ 1 × 10-14 
D) [H3O+]/[OH-] = 1 × 10-14 
E) [H3O+]/[OH-] = 1

As the pH increases, the hydroxide ion concentration ________.

Why do we use the pH scale to indicate the acidity of a solution rather than simply stating the concentration of hydronium ions?

What would be the concentration of hydronium ions in a solution that had a pH = -3? Why would such a solution be impossible to prepare?

Which of the following statements describes a neutral solution?

For the following acid-base reaction, identify what is formed in the space marked. H₂SO₄ + KOH ⇌ KHSO₄ + ???

For the following acid-base reaction, identify what is formed in the space marked. HF + KOH ⇌ ???? + H₂O

What is the source of acid rain?

According to the following reaction, which molecule is acting as a base? H₂O + NH₃ → OH^- + NH₄⁺

According to the following reaction, which molecule is acting as an acid? H₃O⁺ + HSO₄^- → H₂O + H₂SO₄

In the following buffer system, what happens to the concentration of the highlighted molecule if you add acid in the form of H₃O⁺? HF + NaF + H₂O ⇌ F^- + H₃O⁺_{+ Na}+

Would it be easier or harder for a water molecule to donate a hydrogen ion if its polar H-O bond were even more polar? Why?

What results when water, O, reacts with sulfur dioxide, S ?

What would be the best explanation for the fact that most natural water has a pH of about 5.6?

A weak acid is added to a concentrated solution of hydrochloric acid. Does the solution become more or less acidic?

Which of the following statements about strong and weak bases is not true?

Why is phosphoric acid, , a stronger acid than disodium hydrogen phosphate, ?

Cutting back on the pollutants that cause acid rain is one solution to the problem of acidified lakes. Suggest another.

Which of the following statements describes an acidic solution?

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How Atoms Bond

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Exam 10: Acids and Bases in Our Environment

As the pH increases, the hydroxide ion concentration ________.

Why do we use the pH scale to indicate the acidity of a solution rather than simply stating the concentration of hydronium ions?

What would be the concentration of hydronium ions in a solution that had a pH = -3? Why would such a solution be impossible to prepare?

Which of the following statements describes a neutral solution?

For the following acid-base reaction, identify what is formed in the space marked. H2SO4 + KOH ⇌ KHSO4 + ???

For the following acid-base reaction, identify what is formed in the space marked. HF + KOH ⇌ ???? + H2O

What is the source of acid rain?

According to the following reaction, which molecule is acting as a base? H2O + NH3 → OH- + NH4+

According to the following reaction, which molecule is acting as an acid? H3O+ + HSO4- → H2O + H2SO4

In the following buffer system, what happens to the concentration of the highlighted molecule if you add acid in the form of H3O+? HF + NaF + H2O ⇌ F- + H3O+ + Na+

Would it be easier or harder for a water molecule to donate a hydrogen ion if its polar H-O bond were even more polar? Why?

What results when water, O, reacts with sulfur dioxide, S ?

What would be the best explanation for the fact that most natural water has a pH of about 5.6?

A weak acid is added to a concentrated solution of hydrochloric acid. Does the solution become more or less acidic?

Which of the following statements about strong and weak bases is not true?

Why is phosphoric acid, , a stronger acid than disodium hydrogen phosphate, ?

Cutting back on the pollutants that cause acid rain is one solution to the problem of acidified lakes. Suggest another.

Which of the following statements describes an acidic solution?

About Science

Particles of Matter

Elements of Chemistry

Subatomic Particles

The Atomic Nucleus

How Atoms Bond

How Molecules Mix

How Water Behaves

How Chemicals React

Oxidations and Reductions Charge the World

Organic Compounds

Nutrients of Life

Medicinal Chemistry

Optimizing Food Production

Protection Water and Air Resources

Capturing Energy

Filters

For the following acid-base reaction, identify what is formed in the space marked. H₂SO₄ + KOH ⇌ KHSO₄ + ???

For the following acid-base reaction, identify what is formed in the space marked. HF + KOH ⇌ ???? + H₂O

According to the following reaction, which molecule is acting as a base? H₂O + NH₃ → OH^- + NH₄⁺

According to the following reaction, which molecule is acting as an acid? H₃O⁺ + HSO₄^- → H₂O + H₂SO₄

In the following buffer system, what happens to the concentration of the highlighted molecule if you add acid in the form of H₃O⁺? HF + NaF + H₂O ⇌ F^- + H₃O⁺_{+ Na}+