Question

Calculate the molality of ethanol in water in which the mole fraction of ethnol is $0.040$.

• A. $2.315m$
• B. $1.315m$
• C. $3.315m$
• D. $4.315m$

Answer 1

The correct option is A $2.315m$

$X_{ethonol}=0.040;X_{H_{2}O}=0.960\text{Molality}\left(m\right)=\frac{1000\times X_{eth}}{X_{H_{2}O}\times GM{M}_{H_{2}O}}=\frac{1000\times 0.040}{0.96\times 18}=2.315m$