# What is the concentration of hydronium ions in a solution at 25°C with a pH of 4.282?

$5 , 22 {10}^{-} 5 \frac{m o l}{L}$
if pH is difined as$- L o g \left({H}_{3} {O}^{+}\right)$, the concentartion of $\left({H}_{3} {O}^{+}\right)$ is given by ${10}^{- p H}$