NTA Abhyas JEE Main2020ChemistryIonic EquilibriumPractice
If the pK a of acetic acid and pK b of NH 4 OH are 4.76 and 4.75 respectively, what will be the pH of ammonium acetate solution?
Options
- A9.51
- B7.005
- C7.00
- D6.9
Correct answer
B. 7.005
Step-by-step solution
When a weak acid (acetic acid) and weak base NH 4 OH are mixed to form a solution. pH of the solution is then determined by following formula: pH = 7 + 1 2 pK a − pK b Given, pK a   =   4 .76,    pK b   =   4 .75 pH   =   7   +   1 2 4 .76 − 4 .75 pH   =   7   +   0 .005 pH   =   7 .005