5 Steps to a 5 AP Chemistry

1. A solution is prepared by dissolving 1.25 g of an
   unknown substance in 100.0 mL of water.
   Which procedure from the following list could
   be used to determine whether the solute is an
   electrolyte?

(A) Measure the specific heat of the solution.

(B) Measure the volume of the solution.

(C) Measure the freezing point of the solution.

(D) Determine the specific heat of the solution.

(E) Determine the volume of the solute.

2. What is the final K+concentration in a solution
   made by mixing 300.0 mL of 1.0 M KNO 3 and
   700.0 mL of 2.0 M K 3 PO 4?

(A) 1.5 M

(B) 5.0 M

(C) 3.0 M

(D) 2.0 M

(E) 4.5 M

3. Strontium sulfate (SrSO 4 ) will precipitate when a
   solution of sodium sulfate is added to a strontium
   nitrate solution. What will be the strontium ion,
   Sr^2 +, concentration remaining after 30.0 mL of
   0.10 M Na 2 SO 4 solution are added to 70.0 mL of
   0.20 M Sr(NO 3 ) 2 solution?

(A) 0.14 M

(B) 0.15 M

(C) 0.11 M

(D) 0.20 M

(E) 0.030 M

4. Which of the following is a strong electrolyte
   when it is mixed with water?

(A) HNO 2

(B) KNO 3

(C) C 2 H 5 OH

(D) CH 3 COOH

(E) NH 3

5. A solution with a total chloride ion, Cl−, concentra-
   tion of 1.0 M is needed. Initially, the solution is
   0.30 M in MgCl 2. How many moles of solid CaCl 2
   must be added to 400 mL of the MgCl 2 solution to
   achieve the desired concentration of chloride ion?

(A) 0.10

(B) 0.080

(C) 0.20

(D) 0.15

(E) 0.16

6.Assuming the volumes are additive, what is the

final H+(aq) concentration produced by adding

30.0 mL of 0.50 M HNO 3 to 70.0 mL of

1.00 M HCl?

(A) 0.75 M

(B) 1.50 M

(C) 1.25 M

(D) 0.85 M

(E) 0.43 M

7. The molality of a 1.0-molar ethyl alcohol solu-
   tion may be determined if which of the following
   is supplied?

(A) density of the solution

(B) van’t Hoff factor for ethyl alcohol

(C) temperature of the solution

(D) volume of the solution

(E) solubility of ethyl alcohol

8. A solution of chloroform, CHCl 3 , in carbon
   tetrachloride, CCl 4 , is nearly ideal. The vapor
   pressure of chloroform is 170 mm Hg at 20°C,
   and the vapor pressure of carbon tetrachloride is
   87 mm Hg at this temperature. What is the mole
   fraction of carbon tetrachloride in the vapor over
   an equimolar solution of these two liquids?

(A) 0.25

(B) 0.87

(C) 0.66

(D) 0.50

(E) 0.34

Solutions and Colligative Properties  189

 Review Questions

You have 25 minutes to answer the following questions. You will be expected to do your

calculations without a calculator. You may use the periodic table at the back of the book.

For each question, circle the letter of your choice.