Question

When $0.005moles$ of $H_{2}S{O}_4$ is dissolved in $100ml$ of water. What is the approximate $pH$ of the solution?

• A. $1$
• B. $2$
• C. $3$
• D. $4$

Answer 1

The correct option is A $1$

One mole of $H_{2}S{O}_4$ gives $2$ $moles$ of $H^{+}$ ions.

Hence, $0.005$ $moles$ of $H_{2}S{O}_4$ give $0.01$ $moles$ of $H^{+}$ ions.

$\therefore$ Moles of $H^{+}$ ions $=0.01={10}^{-2}$ $mol$

$Volume=100$ $mL={10}^{-1}$ $L$

$\therefore \left[H^{+}\right]=\frac{Moles}{Volume}=\frac{{10}^{-2}}{{10}^{-1}}={10}^{-1}$

$\therefore pH=-\log \left[H^{+}\right]=-\log \left({10}^{-1}\right)=1$

$\therefore pH=1$