Chemistry For Changing Times 14th Edition by Hill - Test Bank

Chemistry For Changing Times 14th Edition by Hill – Test Bank

 

Instant Download – Complete Test Bank With Answers

 

 

Sample Questions Are Posted Below

 

Chemistry for Changing Times, 14e (Hill/McCreary)

Chapter 5   Chemical Accounting

 

5.1   Multiple Choice Questions

 

1) Which one of the following reactions is NOT balanced?

1. A) 2 CO + O2  →  2 CO2
2. B) 2 SO2 + O2  →  2 SO3
3. C) 2 KNO3 + 10 K  →  5 K2O  +  N2
4. D) SF4 + 3 H2O  →  H2SO3  +  4 HF

Answer:  C

Diff: 2      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

2) When the equation below is balanced, the coefficient of aluminum chloride is:

 

AlCl3  +  H2SO4  →  Al2(SO4)3  +  HCl

1. A) 2
2. B) 3
3. C) 1
4. D) 6

Answer:  A

Diff: 3      Var: 4      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

3) Octane (C8H18 ) reacts with oxygen (O2) to form carbon dioxide (CO2) and water (H2O).  When the equation below is balanced, the coefficient of octane is:

 

C8H18  +  O2  →  CO2  +  H2O

1. A) 8
2. B) 25
3. C) 2
4. D) 16

Answer:  C

Diff: 3      Var: 4      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

4) Propane (C3H8 ) reacts with oxygen (O2) to form carbon dioxide (CO2) and water (H2O).  When the equation below is balanced, the coefficient of water is:

 

C3H8  +  O2  →  CO2  +  H2O

1. A) 1
2. B) 4
3. C) 2
4. D) 3

Answer:  B

Diff: 3      Var: 4      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

5) When the equation below is balanced, the coefficient of copper is:

 

Zn  +  CuSO4  →  ZnSO4  +  Cu

1. A) 0
2. B) 1
3. C) 2
4. D) 3

Answer:  B

Diff: 2      Var: 4      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

6) When the equation below is balanced, the coefficient of silver is:

 

Cu  +  AgNO3  →  Cu(NO3)2  +  Ag

1. A) 0
2. B) 1
3. C) 2
4. D) 3

Answer:  C

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

7) When the equation below is balanced, the coefficient of copper(II) nitrate is:

 

Cu  +  AgNO3  →  Cu(NO3)2  +  Ag

1. A) 0
2. B) 1
3. C) 2
4. D) 3

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

8) When the equation below is balanced, the coefficient of silver nitrate is:

 

Cu  +  AgNO3  →  Cu(NO3)2  +  Ag

1. A) 0
2. B) 1
3. C) 2
4. D) 3

Answer:  C

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

9) When the equation below is balanced, the coefficient of oxygen is:

 

Fe  +  O2  →  Fe2O3

1. A) 0
2. B) 1
3. C) 2
4. D) 3

Answer:  D

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

10) When the equation below is balanced, the coefficient of the product is:

 

Fe  +  O2  →  Fe2O3

1. A) 1
2. B) 2
3. C) 3
4. D) 4

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

11) When the equation below is balanced, the coefficient of the hydrogen cyanide, HCN, is:

 

NaCN  +  H2SO4  →  Na2SO4  +  HCN

1. A) 1
2. B) 2
3. C) 3
4. D) 4

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

12) When the equation below is balanced, the coefficient of sodium cyanide is:

 

NaCN  +  H2SO4  →  Na2SO4  +  HCN

1. A) 1
2. B) 2
3. C) 3
4. D) 4

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

13) When the equation below is balanced, the coefficient of sulfuric acid, H2SO4 is:

 

NaCN  +  H2SO4  →  Na2SO4  +  HCN

1. A) 1
2. B) 2
3. C) 3
4. D) 4

Answer:  A

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

14) The following reaction is important in the removal of sulfur dioxide, a major source of acid rain, from the smokestacks of coal burning power plants.  When the equation below is balanced, the coefficient of calcium oxide (commonly called “lime”) is:

 

CaO  +  SO2  +  O2  →  CaSO4

1. A) 1
2. B) 2
3. C) 3
4. D) 4

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

15) The following reaction is important in the removal of sulfur dioxide, a major source of acid rain, from the smokestacks of coal burning power plants.  When the equation below is balanced, the coefficient of calcium sulfate (commonly called “gypsum”) is:

 

CaO  +  SO2  +  O2  →  CaSO4

1. A) 1
2. B) 2
3. C) 3
4. D) 4

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

16) The following reaction is important in the removal of sulfur dioxide, a major source of acid rain, from the smokestacks of coal burning power plants.  When the equation below is balanced, the coefficient of oxygen is:

 

CaO  +  SO2  +  O2  →  CaSO4

1. A) 1
2. B) 2
3. C) 3
4. D) 4

Answer:  A

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

17) Solid lithium hydride reacts with water to form aqueous lithium hydroxide and hydrogen gas.  When this equation is written and balanced, the coefficient of lithium hydride is

1. A) 1.
2. B) 2.
3. C) 3.
4. D) 4.

Answer:  A

Diff: 3      Var: 4      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

18) Tin was among the first metals used by humans.  Elemental tin is produced by heating tin(IV) oxide, the principal ore of tin, with carbon.  The products of this reaction are tin and carbon dioxide.  When the equation is written and balanced, the coefficient of carbon is

1. A) 1.
2. B) 2.
3. C) 3.
4. D) 4.

Answer:  A

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

19) Tin was among the first metals used by humans.  Elemental tin is produced by heating tin(IV) oxide, the principal ore of tin, with carbon.  The products of this reaction are tin and carbon dioxide.  When the equation is written and balanced, the coefficient of tin is

1. A) 1.
2. B) 2.
3. C) 3.
4. D) 4.

Answer:  A

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

20) Ammonia can be prepared by the reaction of magnesium nitride with water.  The products are ammonia and magnesium hydroxide.  When the equation is written and balanced, the coefficient of magnesium nitride is

1. A) 1.
2. B) 3.
3. C) 6.
4. D) 8.

Answer:  A

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

21) Ammonia can be prepared by the reaction of magnesium nitride with water.  The products are ammonia and magnesium hydroxide.  When the equation is written and balanced, the coefficient of magnesium hydroxide is

1. A) 1.
2. B) 3.
3. C) 6.
4. D) 8.

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

 

22) Ammonia can be prepared by the reaction of magnesium nitride with water.  The products are ammonia and magnesium hydroxide.  When the equation is written and balanced, the coefficient of ammonia is

1. A) 1.
2. B) 2.
3. C) 3.
4. D) 6.

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

23) Ammonia can be prepared by the reaction of magnesium nitride with water.  The products are ammonia and magnesium hydroxide.  When the equation is written and balanced, the coefficient of water is

1. A) 1.
2. B) 2.
3. C) 3.
4. D) 6.

Answer:  D

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

24) When oxygen, O2, is passed through an electrical spark (lightning is a good natural source of an electrical spark), ozone, O3, is formed.  When the equation is balanced, the coefficient of ozone is

1. A) 1.
2. B) 2.
3. C) 3.
4. D) 4.

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

 

25) When oxygen, O2, is passed through an electrical spark (lightning is a good natural source of an electrical spark), ozone, O3, is formed.  When the equation is balanced, the coefficient of oxygen is

1. A) 1.
2. B) 2.
3. C) 3.
4. D) 4.

Answer:  C

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

26) The label which indicates that a substance is a gas is

1. A) (g)
2. B) (l)
3. C) (s)
4. D) (aq)

Answer:  A

Diff: 2      Var: 4      Page Ref: Sec. 5.1

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

27) Consider the following equation:  2 Na  +  2 H2O  →  2 NaOH  +  H2

Identify the product(s) for this reaction.

1. A) Na
2. B) Na and H2O
3. C) NaOH
4. D) NaOH and H2

Answer:  D

Diff: 2      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 2: Demonstrate the ability to think critically and employ critical thinking skills.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

28) The total number of each type of atom must be the same on both sides of an equation in order to satisfy the

1. A) Law of Combining Volumes.
2. B) Law of Conservation of Matter.
3. C) Law of Constant Composition.
4. D) Law of Multiple Proportions.

Answer:  B

Diff: 2      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

 

 

29) The observations that gaseous reactants combine to form gaseous products in volume ratios that are simple whole numbers is most directly summarized by which of the following.

1. A) The Law of Conservation of Mass
2. B) The Law of Fixed Proportions
3. C) The Law of Multiple Proportions
4. D) The Law of Combining Volumes

Answer:  D

Diff: 2      Var: 1      Page Ref: Sec. 5.2

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.2  Determine the volumes of gases that react, using a balanced equation for a reaction.

 

30) When 5 liters of hydrogen gas and 2.5 liter of oxygen gas react to form water at a constant temperature and pressure, how many liters of water vapor (steam) will be formed?

2. A) 2.5
3. B) 5
4. C) 3
5. D) .5

Answer:  B

Diff: 3      Var: 4      Page Ref: Sec. 5.2

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.2  Determine the volumes of gases that react, using a balanced equation for a reaction.

31) When 2 liter of nitrogen gas reacts with 6 liters of hydrogen gas at constant temperature and pressure, how many liters of ammonia gas will be produced?

1. A) 2
2. B) 4
3. C) 6
4. D) 8

Answer:  B

Diff: 3      Var: 4      Page Ref: Sec. 5.2

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.2  Determine the volumes of gases that react, using a balanced equation for a reaction.

 

32) When 4 liters of nitrogen gas react with 6 liters of hydrogen gas at constant temperature and pressure, how many liters of ammonia gas will be produced?

1. A) 4
2. B) 6
3. C) 8
4. D) 10

Answer:  A

Diff: 3      Var: 4      Page Ref: Sec. 5.2

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.2  Determine the volumes of gases that react, using a balanced equation for a reaction.

 

33) The explanation of the observations leading to the law of combining volumes is often called “Avogadro’s hypothesis.”  This explanation states that equal volumes of gases at the same temperature and pressure have

1. A) the same number of molecules.
2. B) different numbers of molecules.
3. C) the same reactivity.
4. D) different energies.

Answer:  A

Diff: 2      Var: 1      Page Ref: Sec. 5.2

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.2  Determine the volumes of gases that react, using a balanced equation for a reaction.

 

34) A liter of solid carbon and a liter of oxygen gas at the same temperature and pressure react to produce carbon dioxide.  Using the law of combining volumes, how many liters of carbon dioxide will be produced?

1. A) 1
2. B) 2
3. C) 3
4. D) The law of combining volumes applies only to reactions involving all gases.

Answer:  D

Diff: 3      Var: 1      Page Ref: Sec. 5.2

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.2  Determine the volumes of gases that react, using a balanced equation for a reaction.

35) Which of the following is correct, according to Avogadro’s hypothesis?

1. A) At 0°C and 1 atm pressure, equal volumes of gases contain equal masses.
2. B) At 0°C and 1 atm pressure, equal volumes of gases contain the same number of molecules.
3. C) At 0°C and 1 atm pressure, equal volumes of gases have the same density.
4. D) At 0°C and 1 atm pressure, 1 L of oxygen gas and 1 L of liquid water contain the same number of molecules.

Answer:  B

Diff: 2      Var: 1      Page Ref: Sec. 5.2

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

 

36) Gay-Lussac’s law of combining volumes states that the volumes of reactants and products are in small whole-number ratios.  Which of the following is NOT an assumption for the law of combining volumes?

1. A) The products and reactants must all be gases.
2. B) The products and reactants must all be at the same temperature.
3. C) The products and reactants must all be at the same pressure.
4. D) The products and reactants must all be gases or liquids.

Answer:  D

Diff: 3      Var: 1      Page Ref: Sec. 5.2

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.2  Determine the volumes of gases that react, using a balanced equation for a reaction.

 

37) In order for the law of combining volumes to apply, all of the following must be the same for all reactants EXCEPT

1. A) the pressure must be the same.
2. B) the reactants must be liquids.
3. C) the temperature must be the same.
4. D) all reactants must be gases.

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.2

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.2  Determine the volumes of gases that react, using a balanced equation for a reaction.

 

38) The law of combining volumes applies only to

1. A) gases.
2. B) liquids.
3. C) solids.
4. D) gases and liquids.

Answer:  A

Diff: 2      Var: 1      Page Ref: Sec. 5.2

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.2  Determine the volumes of gases that react, using a balanced equation for a reaction.

39) Avogadro’s number is

6. A) 6.02 × 1023
7. B) 6.02 × 10-23
8. C) 3.02 × 1026
9. D) 2.06 × 1032

Answer:  A

Diff: 2      Var: 1      Page Ref: Sec. 5.3

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.4  Use Avogadro’s number to determine the number of particles of different types in a mass of a substance.

 

40) Avogadro’s number is big.  If you had 6.02 × 1023 dollars, and could spend it at 1 billion (109) dollars per second for your entire life (≈ 75 years), what approximate percentage of your original money would you have left?

1. A) 0%
2. B) 10%
3. C) 50%
4. D) ≈ 100%

Answer:  D

Diff: 2      Var: 1      Page Ref: Sec. 5.3

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.4  Use Avogadro’s number to determine the number of particles of different types in a mass of a substance.

 

 

41) Which of the following has the same number of atoms as 35.4 g of chlorine?

35. A) 35.4 g of germanium
36. B) 19 g of potassium
37. C) 12 g of carbon
38. D) 18 g of water

Answer:  C

Diff: 2      Var: 50+      Page Ref: Sec. 5.3

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.4  Use Avogadro’s number to determine the number of particles of different types in a mass of a substance.

 

42) Which of the following does NOT contain Avogadro’s number of particles?

1. A) 1.0 mole of silver
2. B) 23 g of sodium
3. C) 6.02 × 1023atoms of aluminum
4. D) 12 g of water

Answer:  D

Diff: 2      Var: 36      Page Ref: Sec. 5.3

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.4  Use Avogadro’s number to determine the number of particles of different types in a mass of a substance.

43) Which of the following contains Avogadro’s number of atoms?

15. A) 15.5 g of phosphorus
16. B) 39 g of potassium
17. C) 40 g of bromine
18. D) 100 g of mercury

Answer:  B

Diff: 2      Var: 1      Page Ref: Sec. 5.3

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.4  Use Avogadro’s number to determine the number of particles of different types in a mass of a substance.

 

44) The formula mass of CO2 is

1. A) 28 g/mole.
2. B) 28 u.
3. C) 44 g/mole.
4. D) 44 u.

Answer:  D

Diff: 2      Var: 1      Page Ref: Sec. 5.3

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.3  Calculate the formula mass, molecular mass, or molar mass of a substance.

 

 

45) Which of the following contains as many atoms as 18 g of water, H2O?

1. A) one mole of nitrogen, N2
2. B) three moles of zinc, Zn
3. C) two moles of sodium chloride, NaCl
4. D) two moles of nitrogen, N2

Answer:  B

Diff: 2      Var: 50+      Page Ref: Sec. 5.3

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.5  Convert from mass to moles and from moles to mass of a substance.

 

46) How many moles of sulfur atoms are present in 4.00 moles of CS2?

2. A) 2.00
3. B) 4.00
4. C) 8.00
5. D) 12.00

Answer:  C

Diff: 2      Var: 5      Page Ref: Sec. 5.3

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.5  Convert from mass to moles and from moles to mass of a substance.

 

47) What is the molecular mass of N2O?

1. A) 30 g/mole
2. B) 30 u
3. C) 44 g/mole
4. D) 44 u

Answer:  D

Diff: 3      Var: 1      Page Ref: Sec. 5.3

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.3  Calculate the formula mass, molecular mass, or molar mass of a substance.

48) How many molecules are in 237 g (about a cup) of water?

13. A) 13.1
14. B) 4267
15. C) 6.02 × 1023
16. D) 7.92 × 1024

Answer:  D

Diff: 3      Var: 1      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.4  Use Avogadro’s number to determine the number of particles of different types in a mass of a substance.

 

 

49) Nitroglycerin has a formula C3H5(NO3)3.  The molar mass of nitroglycerin is

1. A) 65 g/mole.
2. B) 227 g/mole.
3. C) 309 g/mole.
4. D) 398 g/mole.

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.3  Calculate the formula mass, molecular mass, or molar mass of a substance.

 

50) Aspirin has a formula C9H8O4.  The molar mass of aspirin is

1. A) 95 g/mole.
2. B) 180 g/mole.
3. C) 220 g/mole.
4. D) 325 g/mole.

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.3  Calculate the formula mass, molecular mass, or molar mass of a substance.

 

51) In the reaction CH4  +  2 O2  →  CO2  +  2 H2O, how many moles of oxygen are required to burn 8.0 g of methane?

1. A) 0.5
2. B) 1.0
3. C) 2.0
4. D) 32

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.6  Calculate the mass or number of moles of a reactant or product from the mass or number of moles of another reactant or product.

52) In the reaction CH4  +  2 O2  →  CO2  +  2 H2O, how many moles of oxygen are required to burn 16.0 g of methane?

1. A) 0.500
2. B) 1.00
3. C) 2.00
4. D) 32.0

Answer:  C

Diff: 3      Var: 1      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.6  Calculate the mass or number of moles of a reactant or product from the mass or number of moles of another reactant or product.

 

 

53) Acetylene (C2H2) burns in pure oxygen with a very hot flame.  The products of this reaction are carbon dioxide and water.  How much oxygen is required to react with 52.0 g of acetylene?

32. A) 32.0 g
33. B) 52.0 g
34. C) 160. g
35. D) 240. g

Answer:  C

Diff: 3      Var: 5      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.6  Calculate the mass or number of moles of a reactant or product from the mass or number of moles of another reactant or product.

 

54) Calcium metal reacts with water to form calcium hydroxide and hydrogen gas.  How many grams of hydrogen are formed when 0.50 g of calcium are added to water?

1. A) 0.025 g
2. B) 0.050 g
3. C) 0.10 g
4. D) 0.50 g

Answer:  A

Diff: 3      Var: 5      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.6  Calculate the mass or number of moles of a reactant or product from the mass or number of moles of another reactant or product.

 

55) Joseph Priestley discovered oxygen in 1774 by heating mercury(II) oxide.  The compound decomposes into its elements.  How much oxygen, O2, is produced by the decomposition of 25 g of HgO?

1. A) 1.8 g
2. B) 3.7 g
3. C) 5.5 g
4. D) none of these

Answer:  A

Diff: 3      Var: 1      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.6  Calculate the mass or number of moles of a reactant or product from the mass or number of moles of another reactant or product.

 

56) Consider the following equation:  N2  +  3 H2  →  2 NH3

Which of the following statements is NOT true for this equation?

2. A) 3 mole of N2reacts with 9 moles of H2.
3. B) 1 L of N2reacts with 3 L of H2.
4. C) 3 gram of N2reacts with 9 grams of H2.
5. D) 2 molecule of N2reacts with 6 molecules of H2.

Answer:  C

Diff: 3      Var: 50+      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.6  Calculate the mass or number of moles of a reactant or product from the mass or number of moles of another reactant or product.

 

57) What is the molar mass of N2O?

1. A) 30 g/mole
2. B) 30 u
3. C) 44 g/mole
4. D) 44 u

Answer:  C

Diff: 3      Var: 1      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.3  Calculate the formula mass, molecular mass, or molar mass of a substance.

 

58) What is the mass of 0.500 mol of NH3?

8. A) 8.50 g
9. B) 3.40 g
10. C) 7.50 g
11. D) 34.0 g

Answer:  A

Diff: 4      Var: 5      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.5  Convert from mass to moles and from moles to mass of a substance.

 

59) How many moles of (NH4)2S are there in 75 g of (NH4)2S?

1. A) 1.04
2. B) 1.10
3. C) 1.50
4. D) 1.56

Answer:  B

Diff: 4      Var: 5      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.5  Convert from mass to moles and from moles to mass of a substance.

 

60) The quantitative relationship between reactants and products in a chemical reaction is

1. A) relative mass.
2. B) percent yield.
3. C) molarity.
4. D) stoichiometry.

Answer:  D

Diff: 1      Var: 1      Page Ref: Sect. 5.4

Global Obj:  Global 2: Demonstrate the ability to think critically and employ critical thinking skills.

Learning Obj:  LO 5.6  Calculate the mass or number of moles of a reactant or product from the mass or number of moles of another reactant or product.

 

61) What is the best way to measure the efficiency of a reaction?

1. A) experimental yield
2. B) percent atom economy
3. C) percent yield
4. D) theoretical yield

Answer:  B

Diff: 3      Var: 1      Page Ref: Sec. 5.4

Global Obj:  Global 2: Demonstrate the ability to think critically and employ critical thinking skills.

Learning Obj:  LO 5.9  Explain how the concept of atom economy can be applied to pollution prevention and environmental protection.

 

62) Atom economy is

1. A) the calculation of the number of atoms conserved in the desired product rather than in waste.
2. B) counting the atoms in the starting material and product.
3. C) having green by-products.
4. D) having green starting materials.

Answer:  A

Diff: 3      Var: 1      Page Ref: Sec. 5.4

Global Obj:  Global 2: Demonstrate the ability to think critically and employ critical thinking skills.

Learning Obj:  LO 5.10a  Calculate the atom economy for chemical reactions.

 

63) A one molar solution is a solution that contains one mole of solute in

1. A) one mole of solvent.
2. B) one liter of solution.
3. C) one kilogram of solvent.
4. D) one kilogram of solution.

Answer:  B

Diff: 2      Var: 1      Page Ref: Sec. 5.5

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.7  Calculate the concentration (molarity, percent by volume, or percent by mass) of a solute in a solution.

 

64) A solution that is 1 molar contains

1. A) six moles of solute in 6 moles of solvent.
2. B) five moles of solute in 5 moles of solution.
3. C) six moles of solute in 600 g of solution.
4. D) four moles of solute in 4 liters of solution.

Answer:  D

Diff: 2      Var: 50+      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.7  Calculate the concentration (molarity, percent by volume, or percent by mass) of a solute in a solution.

 

65) Molarity is a measure of

1. A) the volume of a solution.
2. B) the mass of a substance.
3. C) the ability of a substance to ionize.
4. D) the concentration of a solute in a solution.

Answer:  D

Diff: 2      Var: 1      Page Ref: Sec. 5.5

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.7  Calculate the concentration (molarity, percent by volume, or percent by mass) of a solute in a solution.

 

66) Calculate the number of moles of sodium chloride needed to make 4.0 L of a 3.0 M solution.

1. A) 12 moles of sodium chloride
2. B) 3.0 moles of sodium chloride
3. C) 4.0 moles of sodium chloride
4. D) 7.0 moles of sodium chloride

Answer:  A

Diff: 2      Var: 6      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.8  Calculate the amount of solute or solution given the concentration and the other amount.

 

67) Calculate the number of moles of sodium hydroxide present in 300 mL of a 2.0 M solution of sodium hydroxide.

1. A) 600 moles of sodium hydroxide
2. B) 0.60 moles of sodium hydroxide
3. C) 300 moles of sodium hydroxide
4. D) 0 moles of sodium hydroxide

Answer:  B

Diff: 3      Var: 6      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.8  Calculate the amount of solute or solution given the concentration and the other amount.

 

68) Expressing concentrations in terms of molarity is especially convenient since it allows one to count chemical particles by measuring

1. A) the weights of solutes.
2. B) the weights of solutions.
3. C) the volumes of solvents.
4. D) the volumes of solutions.

Answer:  D

Diff: 3      Var: 1      Page Ref: Sec. 5.5

Global Obj:  Global 2: Demonstrate the ability to think critically and employ critical thinking skills.

Learning Obj:  LO 5.7  Calculate the concentration (molarity, percent by volume, or percent by mass) of a solute in a solution.

 

69) A four molar solution of NaOH in water contains

1. A) four moles of NaOH per liter of solution.
2. B) four grams of NaOH per liter of solution.
3. C) four liters of NaOH per mole of solution.
4. D) four moles of NaOH per mole of solution.

Answer:  A

Diff: 2      Var: 5      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.8  Calculate the amount of solute or solution given the concentration and the other amount.

 

70) The molarity of a solution that contains 0.50 moles of NaOH in 200.0 milliliters of water is

1. A) 0.25 M.
2. B) 0.5 M.
3. C) 1.0 M.
4. D) 2.5 M.

Answer:  D

Diff: 3      Var: 1      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.7  Calculate the concentration (molarity, percent by volume, or percent by mass) of a solute in a solution.

 

71) The molarity of a solution that contains 8.0 g of NaOH in a liter of solution is

1. A) 0.020 M.
2. B) 0.20 M.
3. C) 2.0 M.
4. D) 0.80 M.

Answer:  B

Diff: 4      Var: 5      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.7  Calculate the concentration (molarity, percent by volume, or percent by mass) of a solute in a solution.

 

72) The number of moles of NaOH that are in 250 mL of a 3.0 molar solution is

1. A) 0.25 moles.
2. B) 0.75 moles.
3. C) 1.0 moles.
4. D) 1.5 moles.

Answer:  B

Diff: 5      Var: 1      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.8  Calculate the amount of solute or solution given the concentration and the other amount.

 

73) A solution that is 1% by mass contains

1. A) 3 g of solute in 3 kg of solution.
2. B) 1 g of solute in 100 g of solution.
3. C) 3 mL of solute in 300 mL of solution.
4. D) 2 mole of solute in 2 L of solution.

Answer:  B

Diff: 2      Var: 50+      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.8  Calculate the amount of solute or solution given the concentration and the other amount.

 

74) How many liters of a 0.2 M NaOH solution are needed in order to have 1.0 moles of NaOH?

1. A) 0.2 L
2. B) 0.8 L
3. C) 5 L
4. D) 8 L

Answer:  C

Diff: 3      Var: 5      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.8  Calculate the amount of solute or solution given the concentration and the other amount.

 

75) How many mL of a 4.0% NaOH solution do you need to have 16 g of NaOH?

1. A) 160 mL
2. B) 250 mL
3. C) 400 mL
4. D) 640 mL

Answer:  C

Diff: 3      Var: 1      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.8  Calculate the amount of solute or solution given the concentration and the other amount.

 

76) How many liters of a 0.2 M HCl solution are needed in order to have 1.0 moles of HCl?

1. A) 0.2 L
2. B) 0.8 L
3. C) 5 L
4. D) 8 L

Answer:  C

Diff: 3      Var: 5      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.8  Calculate the amount of solute or solution given the concentration and the other amount.

 

77) A chemist dissolves 9 g of NaCl in 225 mL of water.  Water is the

1. A) solution.
2. B) solute.
3. C) solvent.
4. D) solubility.

Answer:  C

Diff: 1      Var: 36      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

 

78) A solution contains 20 mL of ethanol in a total volume of 100 mL.  The concentration of this solution is

2. A) 2.0 M.
3. B) 2.0 % by mass.
4. C) 20 % by mass.
5. D) 20 % by volume.

Answer:  D

Diff: 3      Var: 1      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.7  Calculate the concentration (molarity, percent by volume, or percent by mass) of a solute in a solution.

 

79) What mass of KOH is needed to make 400.0 mL of 0.725 M KOH?

31. A) 31.0 g
32. B) 101.7 g
33. C) 40.6 g
34. D) 16.3 g

Answer:  D

Diff: 4      Var: 5      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.8  Calculate the amount of solute or solution given the concentration and the other amount.

 

 

5.2   True/False Questions

 

1) The reactants are the starting materials in a reaction.

Answer:  TRUE

Diff: 2      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

2) In an equation, the number in front of a formula is the coefficient.

Answer:  TRUE

Diff: 2      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

3) You can balance a chemical equation by changing the formula of a reactant or a product.

Answer:  FALSE

Diff: 2      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

4) According to Avogadro’s hypothesis, equal volumes of gases at the same temperature and pressure will have the same number of molecules.

Answer:  TRUE

Diff: 2      Var: 1      Page Ref: Sec. 5.2

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.4  Use Avogadro’s number to determine the number of particles of different types in a mass of a substance.

 

5) The formula mass of Na2S is 55 u.

Answer:  FALSE

Diff: 3      Var: 1      Page Ref: Sec. 5.3

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.3  Calculate the formula mass, molecular mass, or molar mass of a substance.

 

6) 50 grams of sodium hydroxide will react with 50 grams of hydrochloric acid to give 50 grams of sodium chloride and 50 grams of water.

Answer:  FALSE

Diff: 3      Var: 9      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.6  Calculate the mass or number of moles of a reactant or product from the mass or number of moles of another reactant or product.

 

7) The molar mass of N2O is 44 u.

Answer:  FALSE

Diff: 3      Var: 1      Page Ref: Sec. 5.4

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.3  Calculate the formula mass, molecular mass, or molar mass of a substance.

 

8) The stoichiometric factor relates the moles of any two substances in a balanced chemical reaction.

Answer:  TRUE

Diff: 3      Var: 1      Page Ref: Sec. 5.4

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.6  Calculate the mass or number of moles of a reactant or product from the mass or number of moles of another reactant or product.

9) An addition reaction will have a higher percent atom economy than a substitution reaction.

Answer:  TRUE

Diff: 2      Var: 1      Page Ref: Sec. 5.4

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.9  Explain how the concept of atom economy can be applied to pollution prevention and environmental protection.

 

10) The percent atom economy is a measure of the proportion of the reactant atoms that become part of the desired product.

Answer:  TRUE

Diff: 2      Var: 1      Page Ref: Sec. 5.4

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.9  Explain how the concept of atom economy can be applied to pollution prevention and environmental protection.

 

11) 600 mL of a 5.0 M solution of sodium hydroxide contains 5.0 moles of sodium hydroxide.

Answer:  FALSE

Diff: 3      Var: 16      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.7  Calculate the concentration (molarity, percent by volume, or percent by mass) of a solute in a solution.

 

12) The molarity (M) of a solution is the number of moles of solute per liter of solution.

Answer:  TRUE

Diff: 2      Var: 1      Page Ref: Sec. 5.5

Global Obj:  Global 1: Demonstrate an understanding of the principles of scientific inquiry.

Learning Obj:  LO 5.7  Calculate the concentration (molarity, percent by volume, or percent by mass) of a solute in a solution.

 

13) When 15 mL of  ethanol is mixed with 55 mL of water, ethanol is the solute.

Answer:  TRUE

Diff: 2      Var: 42      Page Ref: Sec. 5.5

Global Obj:  Global 2: Demonstrate the ability to think critically and employ critical thinking skills.

 

14) The mass percent of a solution that has 0.50 mol of NaOH in 100 g of solution is 5.0%.

Answer:  FALSE

Diff: 3      Var: 5      Page Ref: Sec. 5.5

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.7  Calculate the concentration (molarity, percent by volume, or percent by mass) of a solute in a solution.

 

5.3   Essay Questions

 

1) Balance the equation:  AlCl3  +  H2SO4  →  Al2(SO4)3  +  HCl.

Answer:  2 AlCl3  +  3 H2SO4  →  Al2(SO4)3  +  6 HCl.

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

2) Balance the equation:  C8H18  +  O2  →  CO2  +  H2O

Answer:  2 C8H18  +  25 O2  →  16 CO2  +  18 H2O

Diff: 4      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

3) Balance the equation:  C3H8  +  O2  →  CO2  +  H2O

Answer:  C3H8  +  5 O2  →  3 CO2  +  4 H2O

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

4) Balance the equation:  Zn  +  CuSO4  →  ZnSO4  +  Cu

Answer:  Zn  +  CuSO4  →  ZnSO4  +  Cu

Diff: 2      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

5) Balance the equation:  Cu  +  AgNO3  →  Cu(NO3)2  +  Ag

Answer:  Cu  +  2 AgNO3  →  Cu(NO3)2  +  2 Ag

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

6) Balance the equation:  Fe  +  O2  →  Fe2O3

Answer:   4 Fe  +  3 O2  →  2 Fe2O3

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

 

7) Balance the equation:  NaCN  +  H2SO4  →  Na2SO4  +  HCN

Answer:  2 NaCN  +  H2SO4  →  Na2SO4  +  2 HCN

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

8) Tin was among the first metals used by humans.  Elemental tin is produced by heating tin(IV) oxide, the principal ore of tin, with carbon.  The products of this reaction are tin and carbon dioxide.  Write and balance the equation.

Answer:  SnO2  +  C  →  Sn  +  CO2

Diff: 4      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

9) Ammonia can be prepared by the reaction of magnesium nitride with water.  The products are ammonia and magnesium hydroxide.  Write and balance the equation.

Answer:  Mg3N2  +  6 H2O  →  2 NH3  +  3 Mg(OH)2

Diff: 5      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.

 

10) When oxygen, O2, is passed through an electrical spark (lightning is a good natural source of an electrical spark), ozone, O3 is formed.  Write and balance the equation.

Answer:  3 O2  →  2 O3

Diff: 3      Var: 1      Page Ref: Sec. 5.1

Global Obj:  Global 4: Demonstrate the quantitative skills needed to succeed in chemistry.

Learning Obj:  LO 5.1  Identify balanced and unbalanced chemical equations, and balance equations by inspection.