Questions

The stratosphere layer of the atmosphere is very dry.

Generally, plants absorb dissolved nitrates from soil and convert them into free nitrogen.

• Free nitrogen is simply molecular nitrogen (N2).

• Nitrogen, in its molecular form, consists of two nitrogen atoms bound together with a triple bond.

Proteins are long chains of Amino acids. That is in brief, Amino acids are the monomers of Proteins. Amino acids are compounds which contain both an amino group and a carboxylic group. Proteins are made up of 20 essential amino acids.

Monomer means a small molecule of an organic substance i.e, building block in general.

In the bond formation of barium with oxygen, the valency electrons from the barium transferred to the oxygen and forms an ionic bond.

Projectile

Africa - 54 countries

South America - 12 countries

Antarctica - 0 countries

Europe - 43 countries.

Hence, Antarctica continent has the least countries.