If a non-metal is added to the interstitial sites of a metal,then the metal becomes:

Which of the following compounds is ferroelectric?

Explain paramagnetism and diamagnetism. Write a note on ferromagnetism. Explain antiferromagnetism.

$STATEMENT-1$: Band gap in germanium is small.
$STATEMENT-2$: The energy spread of each germanium atomic energy level is infinitesimally small.

Ionic solids conduct electricity in molten state but not in solid state. Explain.

Solid $CH_4$ is