KVPY2018ChemistryIonic Equilibrium
Among the following, the correct statement is
Options
- Ap H decreases when solid ammonium chloride is added to a dilute aqueous solution of N H 3
- Bp H decreases when solid sodium acetate is added to a dilute aqueous solution of acetic acid
- Cp H decreases when solid N a C l is added to a dilute aqueous solution of N a O H
- Dp H decreases when solid sodium oxalate is added to a dilute aqueous solution of oxalic acid
Correct answer
A. p H decreases when solid ammonium chloride is added to a dilute aqueous solution of N H 3
Step-by-step solution
Dil.aqueous solution of N H 3 is N   H 4 O   H N H 4 O H ⇌ N H 4 + + O H - On adding solid ammonium chloride N H 4 C l ⟶ N H 4 + + C l - The reaction moves backward due to common ion effect. The concentration of O H - decreases and hence the p H decreases.