x. In NaOH solution [OH ] is 2.87 × 10-4. Calculate the pH of solution.
3. Answer the following in brief :
x. In NaOH solution [OH ] is 2.87 × 10-4. Calculate the pH of solution.
Answer:-
Given: \([OH^-] = 2.87 \times 10^{-4}\) M
To find: pH of the solution
Formulae:
i. \(pOH = -\log_{10}[OH^-]\)
ii. \(pH + pOH = 14\)
Calculation:
From formula (i),
\(pOH = -\log_{10}[2.87 \times 10^{-4}]\)
\(= -\log_{10}2.87 - \log_{10}10^{-4}\)
\(= -\log_{10}2.87 + 4 = 4 - 0.4579\)
\(pOH = 3.5421\)
From formula (ii),
\(pH + pOH = 14\)
\(pH = 14 - pOH\)
\(= 14 - 3.5421\)
\(= 10.4579\)
pH of the solution is 10.4579