Question

$4.6$ $c{m}^3$ of methyl alcohol is dissolved in $25.2$g of water with density $0.8$. Calculate $\%$ by mass of methyl alcohol.

• A. $14.72$
• B. $10.67$
• C. $12.74$
• D. $13.45$

Answer 1

Answer: (C)

$12.74$

According to he question:

$\%\left(\frac{w}{W}\right)=\frac{Weightofsolute}{Weightofsolute+weightofsolvent\left(water\right)}\times 100$

Substitutes the values,

$Density=\frac{mass}{volume}$

$mass=0.8\times 4.6=3.68gm.$

$\%bymass=\frac{3.68}{3.68+25.2}\times 100$

$\%=12.74\%bymass$

Hence, option C is correct.