Procedure 1: Apply pH equation The pH of a solution is determined by the equation:\[\text{pH} = -\log[\text{H}^+]\]In this equation, \( [\text{H}^+] \) signifies the molar concentration of hydrogen ions.Procedure 2: Input provided concentration Provided data:- \( [\text{H}^+] = 1 \times 10^{-5} \, \text{mol/L} \).Substituting into the pH equation:\[\text{pH} = -\log(1 \times 10^{-5}) = 5\]Conclusion: Consequently, the solution's pH is 5. The correct selection is option (1).