If a reaction between two solutions results in a suspension, we have a precipitate. The precipitate is solid and [?]. The other product is soluble. The precipitate can be separated by [?], which gets rid of the second product. Then washing the solid material with [?] water leads to a clean product.

This reaction results in a precipitate:

calcium + potassium --> calcium carbonate + potassium nitrate

The calcium carbonate is , while the potassium nitrate is .

Heavy metal cause toxic [?] in the environment. Heavy metal carbonates are insoluble, and form when they react with sodium carbonate.