Question

The numbers of $H^+$ ions present in $1 \,mL$ of a solution whose pH is $13$

• A. $6.022 \times 10^{10}$
• B. $6.022 \times 10^{7}$
• C. $6.022 \times 10^{20}$
• D. $6.022 \times 10^{23}$

Answer 1

Answer: (B)

pH= 13·
$\Rightarrow [H]^+ = 10^{-13} \, mol \, L^{-1}$
$\Rightarrow 1000 \,ml$ solution contains
$ 10^{-13} \times 6.022 \times 10^{23} \, H^+ \, ions$
$ = 6.022 \times 10^{10}H^+ \, ions$
$\therefore $ 1 ml solution contains
$ \frac{6.022 \times 10^{10}}{1000} H^+ ions$
$ = 6.022 \times 10^7 \, H^+ ions$