COMEDK2022ChemistryIonic Equilibrium
pH of 10⁻³ M solution of KOH is.
Options
- A7.01
- B2
- C11
- D9
Correct answer
C. 11
Step-by-step solution
KOH is a strong base, which dissociates completely in aqueous solution as follows: KOH K ⁺ + OH ⁻ The concentration of hydroxide ions is equal to the concentration of the KOH solution: [ OH ⁻] = 10⁻³ M The pOH of the solution is calculated using the formula: pOH = - [ OH ⁻] = - (10⁻³) = 3 Using the relation pH + pOH = 14 at 25^ C : pH = 14 - pOH = 14 - 3 = 11 Answer: 11