Most crystals show good cleavage because their atoms, ions or molecules are:
weakly bonded together.
strongly bonded together.
spherically symmetrical.
arranged in planes.
An ideal gas cannot be liquefied because:
its critical temperature is always above 0oC.
its molecules are relatively smaller in size.
it solidifies before becoming a liquid.
forces operating between its molecules are negligible.
A pure crystalline substance on being heated gradually first forms a turbid liquid at constant temperature, and still at higher temperature turbidity completely disappears. This behaviour is a characteristic of substances forming:
allotropic crystals.
liquid crystals.
isomeric crystals.
isomorphous crystals.
The number of atoms contained in a fcc unit cell of a mono atomic substance is:
1
2
4
6