Question

given a solution with a Ph of 2.8, what is the [H3O+] of the solution?

Answer 1

$pH=-\log_{10} [H_3O^+] \Rightarrow [H_3O^+]=10^{-pH} \\ \\ pH=2.8 \\ \ [H_3O^+]=10^{-2.8} \approx 1.58 \times 10^{-3}$

The [H₃O⁺] of the solution is approximately 1.58 × 10⁻³ M.