Fill in the blanks:

(a) …………… is the most abundant inert gas present in air.

(b) Oxides of sulphur and nitrogen combine with rain water to form …………… and …………… which cause …………… .

(c) …………… and …………… are the most common air pollutants.

(d) …………… discovered the oxygen gas.

(e) Oxygen occupies about …………… of air by volume.

Match the following:

The natural way of adding oxygen to air which involves green plants is called:

1. Photosynthesis
2. Respiration
3. Burning
4. Dissolution

Which one of the following is most likely to be corroded?

1. a stainless steel cup-board
2. a galvanized iron bucket
3. an iron hammer
4. a tin plated iron box