Our Atmosphere (C1)

78% Nitrogen

21% Oxygen

1% Carbon dioxide

The percentage of oxygen in the air can be worked out using a gas syringe. You pass a certain volume of air over hot copper and measure the decrease in volume as the oxygen reacts with it. Gas syringes are used to measure the volume of gas in the experiment. There is some air in the tube with the copper, which will also react with the hot copper causing a small error in the final recording. It is important to let the apparatus cool down at the end of the experiment or the final reading will be too high.

Forming the Earth and Atmosphere:

1. Gravity pulled together particles and formed a very hot earth with no ozone layer. Ultraviolet light hit the earth. Volcanoes spat out major gases; methane, water vapour, carbon dioxide and nitrogen.

2…