Question 1

The oxidation number of carbon in carbon dioxide is

Accepted Answer

A)  +2 
B)  -2 
C)  +4 
D)  -4 
E)  +1

Question 2

Hydroxyapatite, [Ca5(PO4)3(OH)], the major component of tooth enamel, is attacked and decomposed by acids more readily than fluorapatite, [Ca5(PO4)3F]. Which one of the following reactions is analogous to the reaction of hydroxyapatite?

Accepted Answer

A)  Ca(s) + 2HCl(aq) F1F1F1S1F1F1F10F1F1F1S1F1F1F10CaCl2(s) + 2H+ 
B)  CaF2(s) + 2H+(aq) F1F1F1S1F1F1F10F1F1F1S1F1F1F10Ca2+(aq) + 2HF(aq) 
C)  Ca(OH)2(s) + 2H+(aq) F1F1F1S1F1F1F10F1F1F1S1F1F1F10Ca2+(aq) + 2H2O(  ) 
D)  Ca(s) + 2H+(aq) F1F1F1S1F1F1F10F1F1F1S1F1F1F10Ca2+(aq) + H2(g) 
E)  Ca3(PO4)2(s) + 6H+(aq) F1F1F1S1F1F1F10 3Ca2+(aq) + 2H3PO4(aq)

Question 3

Chlorine, ozone, and chlorine dioxide are all common disinfectants for municipal water purification. What chemical property do they all share?

Accepted Answer

A)  They are all strong acids. 
B)  They are all good oxidizing agents. 
C)  They are all good reducing agents. 
D)  They all form precipitates with a wide range of contaminants. 
E)  They are all strong bases.

Question 4

A reaction that takes place between dissolved barium nitrate and dissolved sodium sulfate results in formation of solid barium sulfate. Which equation describes this reaction?

Accepted Answer

A)  Ba(NO3)2(aq) + Na2SO4(aq) F1F1F1S1F1F1F10 BaSO4(s) + 2NaNO3(aq) 
B)  BaNO3(aq) + NaSO4(aq) F1F1F1S1F1F1F10 BaSO4(s) + NaNO3(aq) 
C)  2Ba(NO3)(aq) + Na2SO4(aq) F1F1F1S1F1F1F10 Ba2SO4(s) + 2NaNO3(aq) 
D)  Ba(NO3)2(aq) + 2NaSO4(aq) F1F1F1S1F1F1F10 Ba(SO4)2(s) + 2NaNO3(aq) 
E)  Ba(NO3)2(aq) + Na2SO4(aq) F1F1F1S1F1F1F10 BaSO4(aq) + 2NaNO3(s)

Question 5

Ammonia (NH3) is a weak base that reacts with a strong acid to form the ammonium ion, NH4+. If 5.00 mL of a solution of an ammonia cleaner is titrated directly with 42.6 mL of 0.5000 M HCl, what is the concentration of the NH3 in solution? (Assume that the ammonia is the only solute that reacts with the acid.)

Accepted Answer

A)  0.0587 M 
B)  0.107 M 
C)  4.26 M 
D)  1.07 M 
E)  5.87 M

Question 6

The half-reaction for the reduction of molecular oxygen to water is __________

Accepted Answer

A)   O2(g) F1F1F1S1F1F1F10 H2O(  ). 
B)   O2(g) + H2(g) F1F1F1S1F1F1F10F1F1F1S1F1F1F10H2O(  ). 
C)   O2(g) + H2(g) + 2e- F1F1F1S1F1F1F10F1F1F1S1F1F1F10H2O(  ). 
D)   O2(g) + 2 H+(g) + 2e- F1F1F1S1F1F1F10F1F1F1S1F1F1F10H2O(  ). 
E)   O2(g) + 2 H+(g) F1F1F1S1F1F1F10F1F1F1S1F1F1F10H2O(  ) + 2e-.

Question 7

What is the molar concentration of sodium in a 200.0 mL solution prepared from 1.223 g of sodium phosphate (Na3PO4, 163.9 g/mol), which is a cleaning agent, food additive, and stain remover?

Accepted Answer

A)  0.03731 M 
B)  0.2486 M 
C)  0.7338 M 
D)  0.1119 M 
E)  0.1243 M

Question 8

How many grams of solid magnesium chloride, MgCl2, are needed to make 250 mL of 0.50 M solution?

Accepted Answer

A)  9.5 g 
B)  48 g 
C)  12 g 
D)  125 g 
E)  4.8 g

Question 9

Concentrated sulfuric acid contains 4 g of water for every 100 g of solution. The solvent is __________

Accepted Answer

A)  water. 
B)  sulfuric acid. 
C)  concentrated. 
D)  the same as the solution. 
E)  the same as the solute in this case.

Question 10

Potassium is a very reactive metal. Many of its compounds are not very reactive. For example, some class B fire extinguishers contain potassium bicarbonate as a dry powder for use in extinguishing burning liquids. Why is there such a difference in the reactivity of potassium in the bicarbonate salt and potassium that is a combustible metal?

Accepted Answer

A)  The difference in reactivity really is not that great to warrant an explanation. 
B)  The potassium atom is bonded to an oxygen atom in the bicarbonate salt but is unbonded in the metal and free to react. 
C)  The potassium metal possesses one additional electron that is easily transferred to other substances; the potassium in the bicarbonate salt already has lost this reactive electron. 
D)  The potassium in the bicarbonate salt is a base, but the potassium metal is an acid. 
E)  The potassium in the bicarbonate salt is an acid, but the potassium metal is a base.

Question 11

In which compound does chlorine have an oxidation number of +5?

Accepted Answer

A)  HClO4 
B)  HClO3 
C)  HClO2 
D)  HClO 
E)  HCl

Question 12

How many grams of sodium chloride, NaCl, are needed to make up 1.00 L of a solution that is 2.00 M ?

Accepted Answer

A)  23.0 g 
B)  29.2 g 
C)  58.4 g 
D)  117 g 
E)  35.5 g

Question 13

Which picture best represents an atomic-level view of a nonelectrolyte solution (water molecules not shown)?

Accepted Answer

A)   
B)   
C)   
D)

Question 14

The carbon cycle characterizes the cyclic transformations of the element carbon through the environment and biomass. Some of the important species in this cycle are CO2, CO32-, C6H12O6, and CH4. Which of these compounds would undergo complete oxidation by O2 to give the largest change in oxidation number?

Accepted Answer

A)  CO2 
B)  CO32- 
C)  C6H12O6 
D)  CH4 
E)  CO2 and CO32- are equivalent in this regard.

Question 15

Some microorganisms living under anaerobic conditions extract oxygen from sulfate ions producing hydrogen sulfide gas, which produces a distinctive rotten-egg odor. Write the balanced net ionic equation for this reaction under acidic conditions.

Accepted Answer

The answer of Some microorganisms living under anaerobic conditions extract...

Question 16

A food chemist determined the concentration of acetic acid in a sample of apple cider vinegar. The density of the sample was 1.01 g/mL. The volume of 1.215 M NaOH required to titrate a 25.00 mL sample of the vinegar was 19.85 mL. What is (a) the molar concentration, and (b) the percent by mass of acetic acid in this vinegar? (CH₃COOH, 60.05 g/mol)

Accepted Answer

The answer of A food chemist determined the concentration of...

Question 17

Define the terms oxidizing agent and reducing agent.

Accepted Answer

The answer of Define the terms oxidizing agent and reducing...

Question 18

Water-soluble toxic chromium compounds are waste products of electroplating operations, but the chromium can be precipitated as Cr(OH)3 to remediate the water. How much 1.0 M NaOH solution is needed to remove the chromium from 100 L of a solution that is 0.001 M in Cr3+?

Accepted Answer

A)  100 mL 
B)  300 mL 
C)  10 L 
D)  30 L 
E)  33 L

Question 19

How many liters of 0.200 M NaOH solution are required to completely react with 1.00 L of 0.100 M HCN solution to produce sodium cyanide and water?

Accepted Answer

A)  0.25 L 
B)  0.50 L 
C)  1.00 L 
D)  1.50 L 
E)  2.00 L

Question 20

Identify the acid in the following acid-base reaction. PbCO3(s) + H2SO4(aq) F1F1F1S1F1F1F10 PbSO4(s) + CO2(g) + H2O(  )

Accepted Answer

A)  PbCO3(s) 
B)  CO2(g) 
C)  PbSO4(s) 
D)  H2O(  ) 
E)  H2SO4(aq)

Exam 4: Solution Chemistry and the Hydrosphere

The oxidation number of carbon in carbon dioxide is

Hydroxyapatite, [Ca₅(PO₄) ₃(OH) ], the major component of tooth enamel, is attacked and decomposed by acids more readily than fluorapatite, [Ca₅(PO₄) ₃F]. Which one of the following reactions is analogous to the reaction of hydroxyapatite?

Chlorine, ozone, and chlorine dioxide are all common disinfectants for municipal water purification. What chemical property do they all share?

A reaction that takes place between dissolved barium nitrate and dissolved sodium sulfate results in formation of solid barium sulfate. Which equation describes this reaction?

The half-reaction for the reduction of molecular oxygen to water is __________

What is the molar concentration of sodium in a 200.0 mL solution prepared from 1.223 g of sodium phosphate (Na₃PO₄, 163.9 g/mol) , which is a cleaning agent, food additive, and stain remover?

How many grams of solid magnesium chloride, MgCl₂, are needed to make 250 mL of 0.50 M solution?

Concentrated sulfuric acid contains 4 g of water for every 100 g of solution. The solvent is __________

In which compound does chlorine have an oxidation number of +5?

How many grams of sodium chloride, NaCl, are needed to make up 1.00 L of a solution that is 2.00 M ?

Which picture best represents an atomic-level view of a nonelectrolyte solution (water molecules not shown) ?

Some microorganisms living under anaerobic conditions extract oxygen from sulfate ions producing hydrogen sulfide gas, which produces a distinctive rotten-egg odor. Write the balanced net ionic equation for this reaction under acidic conditions.

Define the terms oxidizing agent and reducing agent.

Water-soluble toxic chromium compounds are waste products of electroplating operations, but the chromium can be precipitated as Cr(OH) ₃ to remediate the water. How much 1.0 M NaOH solution is needed to remove the chromium from 100 L of a solution that is 0.001 M in Cr³⁺?

How many liters of 0.200 M NaOH solution are required to completely react with 1.00 L of 0.100 M HCN solution to produce sodium cyanide and water?

Identify the acid in the following acid-base reaction. PbCO₃(s) + H₂SO₄(aq)  PbSO₄(s) + CO₂(g) + H₂O( )

Exam 4: Solution Chemistry and the Hydrosphere

The oxidation number of carbon in carbon dioxide is

Hydroxyapatite, [Ca5(PO4) 3(OH) ], the major component of tooth enamel, is attacked and decomposed by acids more readily than fluorapatite, [Ca5(PO4) 3F]. Which one of the following reactions is analogous to the reaction of hydroxyapatite?

Chlorine, ozone, and chlorine dioxide are all common disinfectants for municipal water purification. What chemical property do they all share?

A reaction that takes place between dissolved barium nitrate and dissolved sodium sulfate results in formation of solid barium sulfate. Which equation describes this reaction?

The half-reaction for the reduction of molecular oxygen to water is __________

What is the molar concentration of sodium in a 200.0 mL solution prepared from 1.223 g of sodium phosphate (Na3PO4, 163.9 g/mol) , which is a cleaning agent, food additive, and stain remover?

How many grams of solid magnesium chloride, MgCl2, are needed to make 250 mL of 0.50 M solution?

Concentrated sulfuric acid contains 4 g of water for every 100 g of solution. The solvent is __________

In which compound does chlorine have an oxidation number of +5?

How many grams of sodium chloride, NaCl, are needed to make up 1.00 L of a solution that is 2.00 M ?

Which picture best represents an atomic-level view of a nonelectrolyte solution (water molecules not shown) ?

Some microorganisms living under anaerobic conditions extract oxygen from sulfate ions producing hydrogen sulfide gas, which produces a distinctive rotten-egg odor. Write the balanced net ionic equation for this reaction under acidic conditions.

Define the terms oxidizing agent and reducing agent.

Water-soluble toxic chromium compounds are waste products of electroplating operations, but the chromium can be precipitated as Cr(OH) 3 to remediate the water. How much 1.0 M NaOH solution is needed to remove the chromium from 100 L of a solution that is 0.001 M in Cr3+?

How many liters of 0.200 M NaOH solution are required to completely react with 1.00 L of 0.100 M HCN solution to produce sodium cyanide and water?

Identify the acid in the following acid-base reaction. PbCO3(s) + H2SO4(aq)  PbSO4(s) + CO2(g) + H2O( )

Hydroxyapatite, [Ca₅(PO₄) ₃(OH) ], the major component of tooth enamel, is attacked and decomposed by acids more readily than fluorapatite, [Ca₅(PO₄) ₃F]. Which one of the following reactions is analogous to the reaction of hydroxyapatite?

What is the molar concentration of sodium in a 200.0 mL solution prepared from 1.223 g of sodium phosphate (Na₃PO₄, 163.9 g/mol) , which is a cleaning agent, food additive, and stain remover?

How many grams of solid magnesium chloride, MgCl₂, are needed to make 250 mL of 0.50 M solution?

Water-soluble toxic chromium compounds are waste products of electroplating operations, but the chromium can be precipitated as Cr(OH) ₃ to remediate the water. How much 1.0 M NaOH solution is needed to remove the chromium from 100 L of a solution that is 0.001 M in Cr³⁺?

Identify the acid in the following acid-base reaction. PbCO₃(s) + H₂SO₄(aq)  PbSO₄(s) + CO₂(g) + H₂O( )