5. What is the percent by mass of 5.0 g of salt mixed with 80 g of water?
A. 4.9%
B. 7%
C. 3.9%
D. 5.9%

6. What is the percent by volume conceteration of a solution in which 75.0 ml of ethanol is diluted to a volume of 250.0 ml?
A. 20%
B. 40%
C. 25%
D. 30%

7. What volume of acetic acid is present in a bottle containing 350.0 ml of a solution which measures 5.00% concenteration?
A. 16 mL
B. 16.5 mL
C. 17.5 mL
D. 18mL

8. What is the percent by mass of 41. 0 g of NaCl is dissolved in 331 grams of water?
A. 11%
B. 12%
C. 10%
D. 15%

9. A solution is prepared by mixing 15.0 g Na2CO3 and 235 g of H20. calculate the mass percent (%m/m) of the solution.
A. 16%
B. 11%
C. 15%
D. 6%

10. How many grams of NaCl are needed to prepare 225 g of a 10.0% (m/m) NaCl solution?
A. 20 g of NaCl
B. 15 g of NaCl
C. 22.5 g of NaCl
D. 25. 5 g of NaCl​