Question

suggest a test chemical that can be added to the water sample to precipate the lead (II) ions. Show a chemical equation for the formation of the precipate you have chosen.

I chose Hg(N03)2 so
Pb2 + Hg(NO3)2 -->Pb(NO3)2 = Hg

I know I still have to balance it but is my equation right? Thanks so much!

Answer 1

I think what you have shown will not work. There are many Pb^+2 solutions that coexist with Hg(NO3)2. I would suggest adding sulfate ion, chromate ion, chloride ion, iodide ion, bromide ion, carbonate ion, etc for the precipitation of lead(II) ion. The sodium salt would work well; e.g.,

Pb(NO3)2 + NaCl ==> PbCl2 + NaNO3 which still needs to be balanced.