Question

At $740mm$ pressure in a closed vessel. No. of oxygen and hydrogen molecule is same, If oxygen is removed from system than pressure become :

• A. Half of $740mm$
• B. Unchanged
• C. $\frac{1}{9}th$ of $740mm$
• D. Double than $740mm$

Answer 1

The correct option is A Half of $740mm$

$\text{Solution: According to Dalton's law,}$

$P_{\text{Total}}=p_{H_2}+p_{0_2}=740mm$

$\text{Partial Pressure of}$ $H_2\left({PH}_2\right)=\frac{n_{H_2}RT}{V_f}$

$V_f=\text{final Volume of mixture}$

$\text{Pantial pressure of}$ $O_2\left({PO}_2\right)=\frac{{no}_{2}RT}{V_{\rho }}$

$\text{if}{n}_{H_2}=n_0=n$

$\therefore P_{\text{Total}}=\frac{nRT}{V_f}+\frac{nRT}{V_f}$

$\text{if}{0}_2\text{is removed,}$

$p_{0_2}=0$

$p_{\text{Total}}=\frac{nRT}{v_f}$

$\text{by eq. (1) \& (2),}$

$\text{Pressure becomes Half of}740mm$

$\text{Hence option (A) is correct.}$