Question

how many hydrogen ions are present in 1 ml of a solution of PH 13

Answer 1

Since pH = -log10[H+]

then [H+] = 10^-pH

So [H+] = 10^-13 moles/litre

1 ml = 1 * 10^-3 l

And since Avogadro’s number = 6.022 * 10^23 we can calculate the number of H+ ions as:

1 * 10^-13 * 1 * 10^-3 * 6.022 * 10^23 = 6.022 * 10^7 ions