Question
Which of the following mixture gives a buffer solution with pH =9.25 ? Given : pK _ b ( NH _ 4 OH )=4.75
JEE Main
Chemistry
Ionic Equilibrium
2026
JEE Main 2026 (22 January Shift 2)
JEE Main Chemistry Question (2026) — Solution
Options
- A. 0.2 M NH _ 4 OH (0.5 ~L )+0.1 M HCl (0.5 ~L )
- B. 0.2 M NH _ 4 OH (0.4 ~L )+0.1 M HCl (1 ~L )
- C. 0.4 M NH _ 4 OH (1 ~L )+0.1 M HCl (1 ~L )
- D. 0.5 M NH _ 4 OH (0.2 ~L )+0.2 M HCl (0.5 ~L )
Answer
A. 0.2 M NH _ 4 OH (0.5 ~L )+0.1 M HCl (0.5 ~L )
Step-by-step solution
pOH = pK_b + Salt Base 4.75 = 4.75 + Salt Base Milimoles of [Salt] = milimoles of [Base] NH_4OH + HCl NH_4Cl + H_2O 0.2M, 0.5L 0.1M, 0.5L 100 mmole 50 mmole 50 mmole - 50 mmole Milimoles of NH_4OH = milimoles of NH_4Cl
Related: Chemistry — Ionic Equilibrium · All PYQ Banks