Which of the following metallic oxides is antiferromagnetic?

How does doping increase the conductivity of semiconductors?

Solid $CH_4$ is

State the uses of amorphous solids and describe the cleavage property of amorphous solids.

'Stability of a crystal is reflected in the magnitude of its melting points'. Comment. Collect melting points of solid water,ethyl alcohol,diethyl ether and methane from a data book. What can you say about the intermolecular forces between these molecules?

Wax is an example of which type of crystal?