CHEM 1100
Answers to Practice Test 3

Note: Answers are shown in red


1. Which of the following is a weak electrolyte?

a. HCl
b. NH₃
c. C₆H₁₂O₆ (glucose)
d. N₂
e. KCl


2. According to the solubility rules which one of the following is soluble in water?

a. (NH₄)₃PO₄
b. Ca₃(PO₄)₂
c. AlPO₄
d. AgPO₄
e. Mg₃(PO₄)₂


3. In accordance with the solubility rules, which of the folowing rules is true when aqueous solutions of Pb(NO₃)₂ and KI are mixed?

a. KNO₃ will precipitate; Pb²⁺ and I ^- are spectator ions
b. no precipitate will form
c. Pb(NO₃)₂ will precipitate; K⁺ and I ^- are spectator ions
d. PbI₂ will precipitate; K⁺ and NO₃^- are spectator ions
e. Pb²⁺ and I ^- are spectator ions and PbI₂ will precipitate


4. Which is the chemical formula of the salt produced by neutralization of sodium hydroxide and sulfuric acid?

a. NaSO₃
b. Na₂(SO₄)₃
c. Na(SO₄)₂
d. Na₂SO₄
e. Na₃SO₄


5. The oxidation number of Mn in KMnO₄ is:

a. + 8
b. + 7
c. + 5
d. - 7
e. - 8


6. In the following reaction the oxidizing agent is:

5 H₂O₂ + 2 MnO₄^- + 6 H⁺ ---> 2 Mn²⁺ + 8 H₂O + 5 O₂
a. H₂O₂
b. MnO₄^-
c. H⁺
d. Mn²⁺
e. O₂


7. Consider the following solution reaction:

                        AlCl₃ + 3 AgNO₃ ---> 3 Ag Cl + Al (NO₃)₃

What volume of 0.100 M AlCl₃ will exactly react with 55.0 mL of 0.162 M of AgNO₃?

a. 89.1 mL
b. 9.90 mL
c. 46.2 mL
d. 29.7 mL
e. none of the above


8. What is the molarity of a solution that contains 4.0 moles of solute in 2000.0 mL of solution?

a. 0.50 M
b. 1.0 M
c. 2.0 M
d. 4.0 M
e. 10.0 M


9. If 15 grams of sodium nitrate were added to water to make 2.50 liters of solution, what would be the molarity of the resulting solution?

a. 0.17 M
b. 2.3 M
c. 6.0 M
d. 0.071 M
e. 37.5 M


10. If 25.0 mL of a 0.500 M sulfuric acid solution is diluted to 100.0 mL with water, the resulting solution's molarity will be:

a. 2.00 M
b. 1.00 M
c. 50.0 M
d. 0.25 M
e. 0.125 M


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