Question

White lead is heated. The color of its residue on cooling is

Answer 1

Hint: A residue is what remains of a chemical or heavy metal (for example, lead, arsenic, cadmium) inside a plant at some extent in time. The residue could also be the first substance or a derivative (metabolite) of the first substance.

Complete answer:
Lead carbonate may be a white amorphous powder which changes to yellow color on heating (residue is-lead (II) oxide also called litharge or lead monoxide). A colorless and odorless gas is evolved which turns lime water milky.
PbCO₃+Heat→PbO+CO₂
Lead oxide (PbO) also produced, may be a solid of buff yellow color. Thus, the color of residue obtained after thermal decomposition of lead nitrate is yellow.
White lead is extremely poisonous, and painters who apply it are often afflicted with lead colic (see lead poisoning) due to the absorption of too great a quantity into the body. Lead carbonate is employed also in making putty and within the manufacture of certain pottery.
Lead carbonate is manufactured by passing CO₂ into a chilly dilute solution of lead(II) acetate, or by shaking a suspension of a lead salt more soluble than the carbonate with carbonate at a coffee temperature to avoid formation of basic white lead .
Note:
There are many exceptions within the solubility of lead salts like: Lead sulfate is insoluble in cold water whereas most of the sulfates are soluble in cold water. Carbonates are generally insoluble in water but they dissolve in dil.