Name the elements present in calcium oxide ($\mathrm{CaO}$).

Name the elements present in the following compound:

Sugar

State whether the following statements are true or false. If false rewrite the correct form of statements.

A mixture is a pure substance.

State whether the following statements are true or false. If false rewrite the correct form of statements.

Common salt is an element.

State whether the following statements are true or false. If false rewrite the correct form of statements.

The symbol of nitrogen is $\mathrm{N}$

State whether the following statements are true or false. If false rewrite the correct form of statements.

Sugar is a compound made up of three elements, i.e, carbon, hydrogen and oxygen.

State whether the following statements are true or false. If false rewrite the correct form of statements.

${\mathrm{H}}_2$ represents two molecules of hydrogen.

Find out the odd one out. Give reasons for your choice.

Common salt, water, sugar and iron

Find out the odd one out. Give reasons for your choice.

Aluminium, copper, nitrogen and gold