Question

Aqueous solution of glucose was prepared by dissolving $18g$ of glucose in $90g$ of water. The relative lowering of vapour pressure is equal to

• A. $1.1$
• B. $0.0196$
• C. $20$
• D. $196$

Answer 1

The correct option is B $0.0196$

By Raoult's law:

Relative lowering of vapour pressure

$=\frac{\frac{w}{m}}{\frac{w}{m}+\frac{W}{M}}=\frac{18/180}{\frac{18}{180}+\frac{90}{18}}$

$=0.0196$