Question

The solubility of a salt at ${40}^{o}C$ is $25gm$ and at ${100}^{o}C$ it is $75gm$. A saturated solution of $1.5gm$ of the salt is cooled from ${100}^{o}C$ to ${40}^{o}C$. How much salt settle down?

• A. $5gm$
• B. $0.3gm$
• C. $1gm$
• D. $1.2gm$

Answer 1

Answer: (C)

$1gm$

The solubility of salt in hot solvent is 75 gm and in cold solvent is 25 gm.
When a saturated solution containing 75 gm of salt is cooled, $75-25=50$ gm of salt is settled.
When 1.5 gm of saturated salt solution is cooled, the amount of salt settled is $\frac{50}{75}\times 1.5=1$ gm