TTU General Chemistry

----

Chem 111 - Quiz 3B - Fall, 1997
Chapter III: Chemical Reactions & Reactions Stoichiometry

1. Write down the chemical equation for the total combustion of methyl alcohol CH3OH. Balance the chemical equation with the set of smallest whole-number coefficients. What is the coefficient in front of the oxygen species?

a) 1
b) 2
c) 3
d) 4
e) 5

2. Balance the following chemical equation with the set of smallest whole-number coefficients. What is the SUM of the coefficients?

___ K + ___ KNO3 ---> ___ K2O + ___ N2
a) 7
b) 8
c) 10
d) 18
e) 19

3. How many grams of Cl2 are required to completely react with 2.0 grams of H2 in the following chemical reaction?

H2 + Cl2 ---> 2 HCl
a) 70.0 g
b) 35.45 g
c) 2.0 g
d) 4.0 g
e) 140.0 g

4. How many grams of O2 are required to completely oxidize 100.0 grams of Fe in the following chemical reaction?

4 Fe + 3 O2 ---> 2 Fe2O3
a) 57.28 g
b) 42.97 g
c) 76.37 g
d) 21.48 g
e) 75.0 g

5. A synthetic organic chemist wants to make 100.0 grams of benzoyl chloride C7H5OCl from benzoic acid C7H6O2 in the following reaction. How many grams of benzoic acid will be required?

C7H6O2 + SOCl2 ---> C7H5OCl + SO2 + HCl
a) 96.45 g
b) 100.0 g
c) 115.1 g
d) 86.88 g

6. If equal masses of N2 and H2 (7.00 grams each) are combined to produce ammonia NH3, how many grams of ammonia could be produced at maximum yield?

N2 + 3 H2 ---> 2 NH3
a) 3.97 g
b) 7.00 g
c) 14.0 g
d) 8.50 g
e) 4.25 g

7. In the precipitation of BaSO4 reaction, 5.00 grams of BaCl2 are reacted with excess H2SO4 and 4.80 grams BaSO4 are collected by filtration. What is the percent yield of this product?

BaCl2 + H2SO4 ---> BaSO4(s) + 2 HCl
a) 96.0%
b) 85.7%
c) 112%
d) 100%
e) 79.1%

8. A 1.00 gram chunk of Na metal is placed into 100.0 ml of water. What will be the molarity concentration of NaOH produced by complete reaction?

2 Na + 2 H2O ---> 2 NaOH + H2(g)
a) 0.870 M
b) 10.0 M
c) 0.435 M
d) 1.00 M
e) 12.1 M

9. A sample of sulfuric acid is 96.4% H2SO4 by mass. How many grams of sulfuric acid are present in a 20.0 gram sample?

a) 96.4 g
b) 4.82 g
c) 20.0 g
d) 18.7 g
e) 19.3 g

10. A particular solution is 10.0% glucose by mass, and has a specific gravity of 1.11. What mass of glucose is present in 50.0 mL of this solution?

a) 5.55 g
b) 5.00 g
c) 4.50 g
d) 6.12 g

11. How many grams of AgNO3 must I weigh out to prepare 100.0 mL of 0.50 M AgNO3 solution?

a) 2.94 x 10-4 g
b) 0.050 g
c) 5.73g
d) 8.5 g
e) 0.294 g

12. If 5.845 g of NaCl are placed in a 1.00 L flask and the flask is filled with distilled water, what is the molarity of NaCl in the resulting solution?

a) 1.00 M
b) 0.100 M
c) 5.845 M
d) 0.5845 M
e) 10.0 M

13. If 100.0 mL of a 6.0 M HCl solution is diluted to 250.0 mL, what is the molarity of the resulting solution?

a) 2.4 x 10-2 M
b) 15.0 M
c) 2.4 M
d) 6.0 M
e) 1.2 M

14. How many mL of 0.105 M aqueous NaOH solution are required to neutralize 40.0 mL of 0.210 M aqueous H2SO4 solution?

H2SO4 + 2 NaOH ---> Na2SO4 + 2 H2O
a) 10.0 mL
b) 80.0 mL
c) 40.0 mL
d) 20.0 mL
e) 160.0 mL

15. Which of the following is a typical property of a nonmetal?

a) have high thermal conductivity
b) have high electrical conductivity
c) tends to gain electrons to form anions
d) ductile

16. Which of the following elements has the highest metallic character?

a) titanium
b) sodium
c) iron
d) cesium
e) boron

17. Which element is INCORRECTLY matched?

a) phosphorus = metalloid
b) lithium = alkali metal
c) barium = alkaline earth metal
d) fluorine = halogen
e) argon = inert gas

18. Which substance when dissolved in water would give rise to a solution which is HIGHLY conductive?

a) sucrose
b) sodium carbonate
c) methyl alcohol
d) acetic acid
e) glucose

KEY

1)c 2)e 3)a 4)b 5)d 6)d 7)b 8)c 9)e 10)a 11)d 12)b 13)c 14)e 15)c 16)d 17)a 18)b