Question

State two reasons for supposing that brass is a mixture and not a compound.

Answer 1

Brass is a mixture and not a compound can be determined on the basis of following two points:

• Brass is an alloy of Cu and Zn, the amount of Zn can vary in different samples of brass, but a compound has a fixed composition in all the forms.
• Physical methods such as the melting of brass can be used to separate Zn and Cu, as Zn will melt first and upon cooling can be allowed to separate from the Cu crystals, however, a compound cannot be separated by use of the physical process.