Question

The molality of $H_{2}S{O}_4$ solution is $9$. The weight of the solute in $1$ kg $H_{2}S{O}_4$ solution is:

• A. $900.0$ g
• B. $469$ g
• C. $882.0$ g
• D. $9.0$ g

Answer 1

Answer: (B)

$469$ g

Molality of $H_{2}S{O}_4$ solution $=9$ m (given)
$9$ mol $H_{2}S{O}_4$ ($=9\times 98$ g$H_{2}S{O}_4$) is in $1000$g $H_{2}O$
Total mass of $9$ molal $H_{2}S{O}_4$ solution $=1000+(98\times 9)=1882$ g
$1882$ g solution has $H_{2}S{O}_4$ $=882$ g
$1000$ g($=1$ Kg) solution has $H_{2}S{O}_4$$=$ $469$ g