To determine the pH we can apply the equation for the pH of a solution:
pH = -log [H3O+]
Where [H3O+] is the molar concentration of the acid, so now we can apply the equation and do the respective operation:
[tex]\begin{gathered} pH=\text{ -log }\mleft[H_3O+\mright] \\ pH=\text{ -log }\lbrack3.24\times10^{-3}\rbrack \\ pH\text{ = - (-2.49)} \\ pH\text{ = 2.49} \end{gathered}[/tex]