Question

What would be the nature of aqueous solutions of the following salts? (i) \(\mathrm{KNO}_{3}\) (ii) \(\mathrm{Na}_{2} \mathrm{CO}_{3}\) (iii) \(\mathrm{CH}_{3} \mathrm{COONa}\)

Short answer

Question: Determine the nature of the aqueous solutions of the following salts: (i) Potassium nitrate (KNO3), (ii) Sodium carbonate (Na2CO3), and (iii) Sodium acetate (CH3COONa). Answer: (i) The aqueous solution of Potassium nitrate (KNO3) is neutral. (ii) The aqueous solution of Sodium carbonate (Na2CO3) is basic. (iii) The aqueous solution of Sodium acetate (CH3COONa) is basic.

Step-by-step solution

(i) Potassium nitrate (KNO3)

Potassium nitrate dissociates into potassium (K+) and nitrate (NO3-) ions in water. According to the Arrhenius definition, acids are the substances that donate H+ ions, and bases are the substances that donate OH- ions. Potassium ion (K+) is formed from the neutralization of a strong base, KOH (potassium hydroxide), and the nitrate ion (NO3-) is formed from a strong acid, HNO3 (nitric acid). Since both ions are formed from strong acid and strong base, their aqueous solution will be neutral.

(ii) Sodium carbonate (Na2CO3)

Sodium carbonate dissociates into sodium (Na+) and carbonate (CO3^2-) ions in water. The sodium ion (Na+) is formed from the neutralization of a strong base, NaOH (sodium hydroxide), and the carbonate ion (CO3^2-) is formed from a weak acid, H2CO3 (carbonic acid). Since the ions are formed from a strong base and weak acid, their aqueous solution will be basic.

(iii) Sodium acetate (CH3COONa)

Sodium acetate dissociates into sodium (Na+) and acetate (CH3COO-) ions in water. The sodium ion (Na+) is formed from the neutralization of a strong base, NaOH (sodium hydroxide), and the acetate ion (CH3COO-) is formed from a weak acid, CH3COOH (acetic acid). Since the ions are formed from a strong base and weak acid, their aqueous solution will be basic.