MHT CET202411 May 2024Morning ShiftChemistryIonic EquilibriumActual
A buffer solution is prepared by mixing 0.01 M HCN and 0.02 MNaCN . If K _ a for HCN is 6.6 10⁻¹⁰ , what is the concentration of H ⁺ ions in solution?
Options
- A3.3 10⁻⁶ M
- B3.3 10⁻¹⁰ M
- C1.32 10⁻⁶ M
- D1.32 10⁻¹⁰ M
Correct answer
B. 3.3 10⁻¹⁰ M
Step-by-step solution
For an acidic buffer solution, aligned & pH = pK _ a , + ₁₀ [ Salt ] [ Acid ] & pH =- ₁₀ (6.6 10⁻¹⁰ )+ ₁₀ 0.02 0.01 & ( pK _ a =- ₁₀ [ ~K _ a ] ) & pH =9.18+ ₁₀ 2=9.18+0.3010=9.481 & pH =- ₁₀ [ H ⁺ ] & [ H ⁺ ]= Antilog (9.481)=3.3 10⁻¹⁰ M aligned