Answer:
pOH = 1.82
pH = 12.18
Explanation:
pH is defined as - log [H⁺] while pOH is defined as - log [OH⁻]
When you take 30mL of a solution 0.25M of NaOH and complete to 500mL the concentration of NaOH is:
0.25M of NaOH ₓ (30mL / 500mL) = 0.015M of NaOH. As NaOH is a strong base and dissociates completely, the concentration of OH⁻, [OH⁻] is 0.015M. Thus, pOH is:
pOH = - log [0.015M] = 1.82
As 14 = pOH + pH, pH of the solution is:
pH = 14 - 1.82
pH = 12.18
