Question

What is the pH of `10^(-2)` `"M HCl"` solution?

Answer 1

`2`

Explanation:

Because

`["H"^(+)]= 10^-"pH"`

Therefore, the exponent of `10` is the pH and this makes sense because the `"pH"` `(2)` is less than `7`, which indicates that it should be an acid. This is true because `"HCl"` is a strong acid, i.e.

`["H"^(+)] = ["HCl"]`

Answer 2

`2`

Explanation:

Hydrochloric acid is a strong acid which dissociates into single hydrogen `(H^+)` ions in an aqueous solution.

The `"pH"` of a solution is given by the equation,

`"pH"=-log[H^+]`

• `[H^+]` is the hydrogen ion concentration in terms of molarity

And so, we got:

`"pH"=-log[10^-2]`

`=2`