If you had left your copper(II) nitrate/potassium hydroxide precipitate stand for a while, the precipitate would turn into a black powder. The copper doesn't reduce in this reaction, but one mole of water is produced from the reaction of one mole of the copper precipitate.
Predict the product of this decomposition reaction.

Answer is: the equilibrium  shifts toward the reactants, to the left side of chemical reaction.it is because lead(ii) nitrate dissociates in water: pb(no₃)₂ → pb²⁺(aq) + 2no₃⁻(aq).according to lechatelier's principle, the position of equilibrium moves to counteract thechange (more lead cations, common ion), the position of equilibrium will move so that the concentration ofproducts decrease and concentration of reactants of chemical reaction increase.read more on -

The answer you are looking for is option d

Where is the illustration?