Question

A. Calculate the mass percent (m/m) of a solution prepared by dissolving 51.22 g of NaCl in 151.9 g of H2O.

B. Vinegar is a solution of acetic acid in water. If a 265 mL bottle of distilled vinegar contains 19.2 mL of acetic acid, what is the volume percent (v/v) of the solution?

C. Calculate the mass/volume percent (m/v) of 20.5 g NaCl in 75.0 mL of solution.

D. Calculate the molarity (M) of 155.2 g of H2SO4 in 1.330 L of solution.

Answer 1

A) mass percent = mass of solute(g) / mass of solute(g) + mass of solvent(g) *100%

mass percent = 51.22 g / 51.22 + 151.9 *100%

mass percent = 51.22 / 203.12 *100% = 25.2% (m/m)

B ) volume % = volume of solute / volume of solution *100%

volume % (v/v) = 19.2 mL / 265mL *100%

volume % (v/v) = 7.25%

C ) mass / volume (m/v) % = grams of solute / milliliters of solution * 100%

= 20.5 g / 75.0 mL *100% = 27.3 %

D ) use the compound molar mass,which express the weight in grams of 1 mol of substance

155.2g *1 mol of H22SO4 / 98.079 g = 1.58 moles H2SO4

molarity of solution

C = n / V = 1.58 moles / 1.330 L = 1.19 mol / L

C = 1.19 M