Question

A $600$ $ml$ vessel containing oxygen at $800$ $mm$ and a $400$ $ml$ vessel containing nitrogen at $600$ $mm$ at the same temperature are kept in communication with each other through a stop cock. Neglecting the volume of the stop cock, the final pressure of the mixture is:

• A. $1400$ $mm$
• B. $1000$ $mm$
• C. $720$ $mm$
• D. $700$ $mm$

Answer 1

The correct option is C $720$ $mm$

$P=\frac{P_1{V}_1+P_2{V}_2}{V}$

$P=\frac{600\times 800+400\times 600}{1000}=720$ $mm$