How is oil refined?

Q4. How is oil refined?

Ans. Oil drilled from the ground, called crude oil, is separated into different substances, mainly by distillation. This means the crude oil is heated until it evaporates. The substances are then drawn off and condensed from the vapour at different temperatures. The molecules of heavier oils may then be ‘cracked’ by heating under pressure.

How big are atoms.

Q5. How big are atoms?
Atoms are about 10 millionth of a millimeter across and weight 100 trillionths of a trillion of a gram. The smallest atom is hydrogen; the biggest is meitnerium.( since they are so small, atoms are measured in terms of ‘moles’, which is a quantity of the substance containing the same number of atoms as 12 grams of a form of carbon called Carbon 12).