Question

$100$ g of ethyl alcohol-water mixture contains $1$ mol of ethyl alcohol. What is molar ratio of ethyl alcohol and water in the mixture?

• A. $1:3$
• B. $1:4$
• C. $2:3$
• D. None of the above

Answer 1

The correct option is A $1:3$

$1$ mole ethyl alcohol$=46$ g of ethyl alcohol $\left(C{H}_{3}C{H}_{2}OH\right)$
Therefore, water present $=100-46=54$ g
Moles of $C{H}_{3}C{H}_{2}OH=\frac{46}{46}=1$ mol
Moles of $H_{2}O=\frac{54}{18}=3$ mol
$\therefore$ The ratio of ethyl alcohol and water in the mixture is $1:3$.