Define:

(a) Elements

(b) Compounds

Name the main metal present in the following:

(a) Haemoglobin

(b) Chalk

(c) Chlorophyll

(d) Chocolate wrappers

What do you understand by:

(a) Metalloids

(b) Noble gases

Give two examples of each.

Select elements and compounds from the following list:

Iron, plaster of paris, chalk, common salt, copper, aluminium, calcium oxide, cane sugar, carbon, silica, sodium sulphate, uranium, potassium carbonate, silver, carbon dioxide.