Question

What is the pH of a solution with a concentration of 1.8 × 10-4 molar H3O+?

Answer 1

pH is defined as the negative log of Hydrogen ion concentration. Mathematically we can write this as:

$pH=-log[H^{+}]=-log[H_{3}O]$

We are given the concentration of $H_{3}O$. Using the value in formula, we get:

$pH=-log[1.8*10^{-4}]=3.745$

Therefore, the pH of the solution will be 3.745