Answer:
The pH of the solution is 4 and it is acidic.
Explanation:
To calculate the pH knowing the concentration of H3O+, it is necessary to use the pH formula:
[tex]\begin{gathered} pH=-log\lbrack H_3O^+\rbrack \\ pH=-log(1.0*10^{-4}) \\ pH=4 \end{gathered}[/tex]So, the pH of the solution is 4. Since the pH value is less than 7, the solution is acidic.