Question

The $pH$ of a mixture of $0.01MHCl$ and $0.1MC{H}_{3}COOH$ is approximately

• A. $1$
• B. $2$
• C. $4$
• D. $7$

Answer 1

Answer: (A)

$1$

Solution:- (A) $1$

$\left[H^{+}\right]={10}^{-2}$

$\left[{OH}^{-}\right]={10}^{-1}$

${\left[H^{+}\right]}_f=\frac{{10}^{-2}\times 1000+{10}^{-1}\times 1000}{1000+1000}=5\times {10}^{-2}$

Therefore,

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

$\Rightarrow pH=-\log (5\times {10}^{-2})\approx 1$