Identify Common Chemical Names

The question asks for the common name of Zinc sulfate heptahydrate, chemically represented as $ZnSO₄.7H₂O$.

Compound Identification

Zinc sulfate heptahydrate ($ZnSO₄.7H₂O$) is historically and commonly known as white vitriol.

Distinguishing Related Compounds

It is important to distinguish this from other similar chemical names:

• Blue Vitriol is the common name for Copper(II) sulfate pentahydrate ($CuSO₄.5H₂O$).
• Gypsum is Calcium sulfate dihydrate ($CaSO₄.2H₂O$).
• Epsom salt is the common name for Magnesium sulfate heptahydrate ($MgSO₄.7H₂O$).

Therefore, the correct common name for $ZnSO₄.7H₂O$ is white vitriol.