# 62) What is the mass percent of hydrogen in water

```62) What is the mass percent of hydrogen in water?
A) 33.3
B) 88.8
C) 5.60
D) 11.2
E) none of the above
63) What is the mass percent of chlorine in hydrochloric acid?
A) 2.8
B) 35.5
C) 97.2
D) 70.1
E) none of the above
82) How many moles of oxygen are in 3.70 moles of NaClO 4?
A) 3.70
B) 0.270
C) 21.5
D) 14.8
E) none of the above
83) What is the mass percent of Mg in MgCl2?
A) 12.3
B) 40.7
C) 25.6
D) 68.3
E) none of the above
85) Given that sodium chloride is 39.0% sodium by mass, how many grams of sodium chloride are needed
to have 750. mg of Na present?
A) 1.92
B) 0.293
C) 1,920
D) 29.3
E) none of the above
47) We dissolve 2.45 g of sugar in 200.0 g water. What is the mass percent of sugar in the solution?
A) 1.21%
B) 1.23%
C) 2.42%
D) 123%
E) none of the above
48) A solution contains 100.0 g water, 10.0 g NaCl, and 15.0 g methanol. What is the weight percent of
methanol in the solution?
A) 8.00%
B) 10.0%
C) 12.0%
D) 15.0%
E) none of the above
53) How many moles of NaF are in 34.2 grams of a 45.5% by mass NaF solution?
A) 0.814
B) 75.2
C) 15.6
D) 0.371
E) none of the above
54) What is the molarity of a solution prepared by dissolving 10.7 g NaI in 0.250 L?
A) 42.8
B) 0.0714
C) 2.86 x 10-4
D) 0.286
E) none of the above
57) A 90.0 g sample of NaOH is dissolved in water and the solution is diluted to give a final volume of
3.00 liters. The molarity of the final solution is:
A) 0.500 M
B) 0.750 M
C) 1.00 M
D) 2.25 M
E) none of the bove
62) What is the final concentration of a solution prepared by diluting 35.0 mL of 12.0 M HCl to a final
volume of 1.20 L?
A) 0.504 M
B) 3.50 M
C) 0.420 M
D) 0.350 M
E) none of the above
63) What volume of 12.0 M HCl is required to make 75.0 mL of 3.50 M HCl?
A) 21.9 mL
B) 0.560 mL
C) 257 mL
D) 560. mL
E) none of the above
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