The pH of 10–8 M aqueous HCl is

When the concentration of the acid or base is less than equal to 10-7 M, then the [H+] or [OH-] coming from water is also taken into account to determine the PH of the solution.H+=10-8 Mfrom HCl+10-7 Mfrom water H+=1.1×10-7 M ;pH = 7 – log1.1 = 6.98 ;