Answer
is: pH value of solution is 11.85.
[OH⁻] = 7.1·10⁻³ M; equilibrium concentration of hydroxide anions.
[OH⁻]·[H⁺] = Kw.
0.0071 mol/L · [H⁺] = 10⁻¹⁴ mol²/L².
[H⁺] = 10⁻¹⁴ mol²/L² ÷ 7.1·10⁻³ mol/L.
[H⁺] = 1.4·10⁻¹² mol/L.
pH = -log[H⁺].
pH = -log(1.4·10⁻¹² mol/L).
pH = 11.85.
If pH is less than seven, solution is acidic; greater than seven, solution is basic; equal seven, solution is neutral.
