MCQ
How many $H^+$ ions are present in $2\, mL$ of a solution whose $pH$ is $13$ ?
  • A
    ${10^{ - 16}}$
  • $12.04 \times {10^7}$
  • C
    $6.02 \times {10^7}$
  • D
    $12.04 \times {10^{13}}$

Answer

Correct option: B.
$12.04 \times {10^7}$
b
$pH=13 \quad[H^+]=10^{-13} \,M$

Moles $=$ Molarity $\times V$ inlitre

$=\quad 10^{-13} \times \frac{2}{1000}$

$=\quad 10-13 \times 2 \times 10^{-3}$

$=\quad 2 \times 10^{-16}$

no. of $H^+$ ions $=2 \times 10^{-16} \times 6.023 \times 10^{23}$

$=12.046 \times 10^7$

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