A solution of methanol in water is 20 % by volume. If the solution and pure methanol have densities of 0.964 kg L-1 and 0.793 kg L-1, respectively, find the percent of methanol by weight?

Question

A solution of methanol in water is 20 % by volume. If the solution and pure methanol have densities of 0.964 kg L-1 and 0.793 kg L-1, respectively, find the percent of methanol by weight? (A) 15.8 (B) 16.45 (C) 20 (D) 14.8

Tardigrade Admin · Accepted Answer

Given, methanol =20 mL Water =8 mL density of methanol =0.793 kg L -1 or 0.793 gmL -1 density of solution =0.964 kg L -1 or 0.964 gmL -1 As, density =( text mass / text volume ) ∴ mass/weight of methanol =0.793 g mL -1 × 20 mL =15.86 g Similarly weight of solution =0.964 g mL -1 × 80 mL =96.4 g We know that, % by weight =( text weight of solute / text weight of solution ) × 100 =(15.86 g /96.4 g ) × 100=16.45

Q. A solution of methanol in water is $20%$ by volume. If the solution and pure methanol have densities of $0.964 k g L^{- 1}$ and $0.793 k g L^{- 1}$ , respectively, find the percent of methanol by weight?

15.8

16.45

20

14.8

17.6

Q. A solution of methanol in water is 20% by volume. If the solution and pure methanol have densities of 0.964kgL−1 and 0.793kgL−1, respectively, find the percent of methanol by weight?

15.8

16.45

20

14.8

17.6

Q. A solution of methanol in water is $20%$ by volume. If the solution and pure methanol have densities of $0.964 k g L^{- 1}$ and $0.793 k g L^{- 1}$ , respectively, find the percent of methanol by weight?