What is the pH of an aqueous solution with the hydronium ion concentration : [H3O+] = 6.3 x 10-6 M?

pH = 5.2

Explanation:

pH of a solution is defined as the concentration of hydrogen ion in a solution. It is also the negative logarithmic value of the concentration of hydrogen ion. It determines the acidity or alkalinity of a solution.

HA (aq) + H2O (l) - -> A - (aq) + H3O + (aq)

pH = - log[H3O+]

= - log [6.3 x 10-6]

= 5.200