Question

Compared with a basic solution of pH12 the same volume of an acidic solution at pH 4 has how many times more hydrogen ions. Show how you derived this figure .

Can you explain it step by step thx :)

Answer 1

See we know that

pH= -log[H+] (base 10)

First find the concentrations of [H+] using the pH values given in the question. And then take the ratio of the two [H+] concentrations to find out how many times more hydrogen ions corresponds to pH 4.

so if pH is 12,

12 = -log[H+]

[H+] = antilog[-12]

[H+] = 1 x 10^-12 -(1)

Similarly find the concenration of [H+] for pH = 4

4 = -log[H+]'

[H+]' = antilog[-4]

[H+]' = 1 x 10^-4 -(2)

divide (1) by (2)

[H+]' / [H+] = 1 x 10^-4 / 1 x 10^-12

[H+]' = 10^8  [H+]

So the concentration of [H+] ions at pH 4 is 10^8 times more than the concentration of [H+] at pH 12.