Answer is: concentration of hydrogen cations is 6.6·10⁻¹² M.
pH = 11.18.
pH = -log[H+].
[H+] = 10∧(-pH).
[H+] = 10∧(-11.18).
[H+] = 6.6·10⁻¹² mol/L.
pH value (potential of hydrogen - [H+]) is a logarithmic scale that specify the acidity or basicity of an aqueous solution. When pH is greater than seven, aqueous solution is basic, below seven is acidic and when pH is equal seven, solution is neutral.
