Will a precipitate form (yes or no) when 50.0 ml of 1.2 × 10–3 m pb(no3)2 are added to 50.0 ml of 2.0 × 10–4 m na2s? if so, identify the precipitate.

Yes, a precipitate of PbS forms

Explanation:

The equation of the reaction is given as:

                   Pb(NO₃)₂ + Na₂S → PbS + 2NaNO₃

The lead sulfide forms a precipitate in the aqeous solution.

Precipitation is a form of reaction in which ions combines to form a solid precipiate. Most double displacement reactions in which ionic compounds are the reactants results in formation of a precipitate as the product.

There are rules of solubility which guides a reaction that would lead to the formation of a precipitate. The mos applicable of the rules to the reaction stated above is that "carbonates, phosphates, sulfides, oxides and hydroxides are insolube". The sulfide of lead formed in the product is therefore insoluble.