The ability of a given substance to assume two or more crystalline structures is called:

Wax is an example of which type of crystal?

Give the classification of crystalline solids.

Solid methane is

What type of semiconductor is obtained by doping $Si$ with $B$ $(Al, Ga)$?

Soldiers of Napoleon's army while at the Alps during a freezing winter suffered a serious problem regarding the tin buttons of their uniforms. White metallic tin buttons got converted to grey powder. This transformation is related to