4. What is the nature of the aqueous solution of Pb(NO3)2? Justify your answer by labeling the process with a condensed ionic equation. How will the pH of the medium change if the solution is heated,​

Ответ:

The aqueous solution of Pb(NO3)2 is acidic in nature because the nitrate ion (NO3-) is a weak conjugate base of a strong acid (HNO3), which can hydrolyze in water to produce H+ ions.

The ionic equation for the dissociation of Pb(NO3)2 in water is as follows:

Pb(NO3)2 (s) → Pb2+ (aq) + 2NO3- (aq)

In this equation, Pb(NO3)2 dissociates into Pb2+ and NO3- ions when it dissolves in water. These ions can interact with water molecules to produce H+ and OH- ions. However, since Pb2+ ions can react with OH- ions to form an insoluble precipitate of Pb(OH)2, the hydrolysis reaction is shifted towards the formation of H+ ions. Therefore, the aqueous solution of Pb(NO3)2 is acidic.

If the solution is heated, the solubility of Pb(OH)2 will decrease, and the concentration of OH- ions will decrease. This will cause the pH of the medium to decrease, making the solution more acidic.