Question

A solution has a [OH−] of 1 x 10−12 M. What is the [H3O+] of the solution? a1 x 10−14 M b1 x 10−2 M c2 M d14 M

Answer 1

Answer:

b. 1 x 10⁻² M.

Explanation:

Let's see the following formula, which represents the dissociation constant:

$[OH^-]=[H_3O^+]=1\cdot10^{-7}\text{ M}.$

If we multiply each [OH -] and [H3O +] concentrations, we obtain:

$[OH^-][H_3O^+]=1\cdot10^{-14}\text{ M}^2.$

As we have [OH -] = 1 x 10⁻¹² M, if we solve for [H3O +] and replace the value of the concentration of [OH -] we obtain:

$[H_3O^+]=\frac{1\cdot10^{-14}M^2}{[OH^-]}=\frac{1\cdot10^{-14}M^2}{1\cdot10^{-12}M}=1\cdot10^{-2}M=0.01\text{ M.}$

The [H3O +] of the solution would be b. 1 x 10⁻² M.