Question

$10ml$ of $\frac{M}{200}{H}_{2}S{O}_4$ is mixed with $40ml$ of $\frac{M}{200}{H}_{2}S{O}_4$. The $pH$ of resulting solution is :

• A. $2.301$
• B. $2$
• C. $1.301$
• D. $1$

Answer 1

The correct option is B $2$

According to the problem:-

Let us consider the molarity of the acids are same pH is independent of the volume of the solution.

$\left(\frac{M}{200}\right)$ or $0.005$ M solution is ,

Let us consider the $H_{2}S{o}_4$ is a dibasic acis, it dissociates as

$H_{2}S{o}_4\to 2H^{+}S{o_4}^2$

Therefore

$\left[H^{+}\right]=2\times 0.005$

$=0.01M$

Hence,

$pH=-\log \left[H^{+}\right]$

$=-\log \left[0.01\right]$

$=2$