San Jacinto College - CHEM 1311

1411 Fall 2016 Exam II

1)(c) What is the total mass (amu) of carbon in C₁₂H₁₀O₆ ?

a)     144.12 amu

1. 2. 60.05 amu
   3. 12.09 amu

d)   342.29 amu

e)   34.89 amu

2. 13(d) What is the molar mass of CH₃COCH₃ ?

a)     72.15 g/mol

b)    378.10 g/mol

c)     256.67 g/mol

4. 58.08 g/mol
5. 41.77 g/mol

3. 18(a) Determine the number of moles of 2.12 g of potassium bromide, KBr.

a)     7.7 × 10³ mol

b)   6.51 × 10⁵ mol

c)     1.8 x 10^-2 mol

d)    2.61 × 10⁵ mol

e)    2.56 × 10⁴ mol

4. 22(a) A 55-kg woman has 7.5 × 10^–3 mol of hemoglobin (molar mass = 64,456 g/mol) in her blood. What is this quantity in grams?

a)     5.6 x 10⁴ g

b)    7.7 × 10³ g

c)     4.8 × 10² g

d)  5.6 x 10⁴ g

e)  9.6 x 10³ g

5. 26 Diamond is one form of elemental carbon. An engagement ring contains a diamond weighing 1.25 carats (1 carat = 200 mg). How many atoms are present in the diamond?

1. 1.25 x 10²² Atoms
2. 7.27 x 10²³ Atoms
3. 6.65 x 10²⁰ Atoms
4. 8.77 x 10²² Atoms
5. 7.22 x 10²³ Atoms

6. 47(e) Determine the molarity for 7.0 × 10^–3 mol of I₂ in 100.0 mL of solution

a)     0.196 M

b)   6.23 M

c)     209.4 M

d)    0.070 M

e)   3.84 M

7. 51(a) Calculate the mass of the solute in 2.00 L of 18.5 M H₂SO₄, concentrated sulfuric acid.

a)     3.703 × 10² g H₂SO₄

b)    3.334 × 10³ g H₂SO₄

c)     6.988 × 10³ g H₂SO₄

d)   3.63 x 10³ g H₂SO₄

e)   7.783 × 10⁴ g H₂SO₄

8. 53 What is the molarity of KMnO₄ in a solution of 0.0908 g of KMnO₄ in 0.500 L of solution?

a)     2.72 × 10^-2 M

b)    1.15 x 10^-3 M

c)     6.3 × 10^-3 g M

d)   3.63 x 10^-2 M

e)   7.783 × 10^-4 M

9. 58 What volume of a 1.00-M Fe(NO₃)₃ solution can be diluted to prepare 1.00 L of a solution with a concentration of 0.250 M?

a)     0.215 L

b)    0.233 L

c)     0.250 L

d)    0.260 L

e)    0.283 L

10. 60 If 4.12 L of a 0.850 M-H₃PO₄ solution is be diluted to a volume of 00 L, what is the concentration the resulting solution?

a)     0.115 M

b)    0.435 M

c)     0.259 M

d)    0.350 M

e)    0.883 M

11. Indicate what type, or types, of reaction the following represents:

2KClO₃(s)

− −?

2KCl(s) + 3O₂ ( g)

1. combustion

2. oxidation-reduction
3. neutralization
4. precipitation
5. ionic

12. 42 (a) Write the balanced equation, then calculate the mass of chlorine, Cl₂, required to react with
    0. g of sodium metal, Na, to produce sodium chloride, NaCl.

12. 1. 1. 15.4 g Cl₂
       2. 35.2 g Cl₂
       3. 56.4 g Cl₂
       4. 76.9 g Cl₂
       5. 98.7 g Cl₂
13. 44 (a) Write the balanced equation, then determine the mass of Mg required to react with 5.00 g of HCl and produce MgCl₂ and H₂.

1. 0.56 g Mg
2. 0.78 g Mg
3. 1.67 g Mg
4. 4.58 g Mg
5. 8.99 g Mg

14. 46 H₂ is produced by the reaction of 118.5 mL of a 0.8775-M solution of H₃PO₄ according to the

following equation: 2Cr + 2H3PO4

− −?

3H2   + 2CrPO4 . Determine the mass of H₂ produced.

a)     0.0167 g H₂

b)    0.3144 g H₂

c)     0.7874 g H₂

d)    1.113 g H₂

e)    1.563 g H₂

15. 47 Gallium chloride is formed by the reaction of 2.6 L of a 1.44 M solution of HCl according to the

following equation: 2Ga + 6HCl

produced.

1. 0.12 x 10² g GaCl₃
2. 1.6 x 10² g GaCl₃
3. 2.2 x 10² g GaCl₃
4. 7.7 x 10³ g GaCl₃
5. 5.1 x 10³ g GaCl₃

− −?

2GaCl3 + 3H2 . Determine the mass of gallium chloride

16. 50 What mass of silver oxide, Ag₂O, is required to produce 25.0 g of silver sulfadiazine, AgC₁₀H₉N₄SO₂, from the reaction of silver oxide and sulfadiazine:

2C10 H10 N4SO2  + Ag2O

− −?

2AgC10 H9 N4SO2   +  H2O

1. 2.22 g Ag₂O
2. 3.41 g Ag₂O
3. 5.99 g Ag₂O
4. 8.11 g Ag₂O
5. 9.62 g Ag₂O

17. 52 Automotive air bags inflate when a sample of sodium azide, NaN₃, is very rapidly decomposed:

2NaN₃ (s)

− −?

2Na(s)

+ 3N₂ (g)

What mass of sodium azide is required to produce 2.6 ft³ (73.6 L) of nitrogen gas with a density of 1.25 g/L?

1. 132 g NaN₃
2. 197 g NaN₃
3. 561 g NaN₃
4. 141 g NaN₃
5. 948 g NaN₃

18. 56 What volume of a 0.750 M solution of hydrochloric acid, a solution of HCl, can be prepared from the HCl produced by the reaction of 25.0 g of NaCl with an excess of sulfuric acid:

NaCl(s)

+  H2SO4 (l)

− −?

HCl(g)

+ NaHSO₄ (s)

1. 0.121 L HCl
2. 0.270 L HCl
3. 0.570 L HCl
4. 0.791 L HCl
5. 0.998 L HCl

19. 68 In a laboratory experiment, the reaction of 3.0 mol of H₂ with 2.0 mol of I₂ produced 1.0 mol of HI. Determine the percent yield for this reaction.

a)     0.2%

b)   55%

c)     3.0%

d)    78%

e)    25%

20. 90 What volume of a 0.00945-M solution of potassium hydroxide would be required to titrate 50.00 mL of a sample of acid rain with a H₂SO₄concentration of 1.23 ×10^–4 M.

H₂SO₄ (aq) +

2KOH(aq)

− −?

K₂SO₄ (aq) +

2H₂O(l)

a)     9.88 L

b)   0.694 L

c)     0.0776 L