Chemistry 101        Quiz 9A        11/9/98   Dr. B. Jackson

131. A solution contained 30 mL of water and 70 mL of alcohol.  Which one is the solvent?
     a) alcohol      b) water

132.  An increase in temperature will generally __________ the amount of gas dissolved in a         
         liquid.
     a) increase      b) decrease

133. What is the percent concentration (m/v) if 20 grams of NaCl (MW 58.5) were brought up to
        a 250 mL volume with water?
     a) 20%      b) 10%     c)  8%      d) 34%

134.   How many grams of NaCl (MW 58.5) are present in 30 mL of a 5% (m/v) solution?
     a) 15      b) 29.3    c) 5    d) 1.5

135.  What volume of a 30% solution of NaOH (MW 40) would contain 4 grams of NaOH?
     a) 13.3 mL    b) 120 mL     c) 10 mL     d) 12 mL

136.  What is the percent concentration (m/m) of a solution that had 50 grams of NaOH (MW 40) 
         in 100 grams of water?
     a) 50%     b) 33%    c) 20%    d) 2%

137.  What is the molarity of a solution which has 10 grams of NaOH (MW 40) in 100 mL of
         solution?
     a) 10 M     b) 4 M     c) 2.5 M      d) 25 M

138.  What volume of a 2 M NaOH (MW 40) would contain 1 gram of NaOH?
     a) 12.5 mL    b) 25 mL     c) 50 mL    d) 40 mL    e) 80 mL

139.  How many grams of NaOH would be needed to make up 80 mL of a 4 M solution?
     a) 5      b) 12.8     c) 32     d) 128

140.  How many milligrams are present in 50 mL of a 5 mg% solution?
     a) 2.5     b) 0.25    c) 5    d) 10


Ans: 131a; 132b; 133c; 134d; 135a; 136b; 137c; 138a; 139b; 140a