Question

Where the (s) indicates that K_2CrO_4 is a solid. A soluble lead compound when dissolved in water will form anions and lead cations, Pb^2+. If a weighed sample of a soluble lead salt is dissolved in water and mixed with a solution containing CrO_4^2− a chemical reaction occurs and pure PbCrO_4, an orange solid of known composition, forms. The net ionic equation for this reaction is"

In the given chemical reaction, what is the net ionic equation for the formation of pure PbCrO4, an orange solid?
A) Pb^2+ + CrO_4^2- → PbCrO_4(s)
B) 2Pb^2+ + CrO_4^2- → Pb_2CrO_4(s)
C) Pb^2+ + 2CrO_4^2- → PbCr_2O_8(s)
D) 2Pb^2+ + 2CrO_4^2- → 2PbCrO_4(s)

Answer 1

The net ionic equation for forming pure PbCrO4 is given by Pb^2+ + CrO4^2- → PbCrO4(s), representing the formation of a precipitate from a lead cation and a chromate anion.

Step-by-step explanation:

The net ionic equation for the formation of pure PbCrO4, an orange solid, from a reaction between a soluble lead salt and a solution containing CrO42− is:

Pb2+ + CrO42− → PbCrO4(s)

This reaction shows the lead cation combining with the chromate anion to form lead chromate, a precipitate. This process is a common substitution reaction used to prepare an insoluble salt from soluble reactants.