Reacting Gas Volumes
AIM: to investigate the relationship between the volumes of gases involved in a reaction.
HYPOTHESIS: A new gas will form when two gases will react together.
Nitric oxide and oxygen are both colourless gases which do not dissolve in water. However, when they mix they form a different gas called nitrogen dioxide which is brown, soluble in water and has a particular odour. This is an example of two gases reacting together to produce a complete new gas.
In this experiment you will mix nitric oxide and oxygen in varying volumes and measure the volume of nitrogen dioxide produced in each case. From these measurements a simple relationship should emerge. Measurements of the volumes in gaseous reactions like this led to the modern definition of the terms ‘atom’ and ‘molecule’.
- Plastic tub or bucket
- 100 mL measuring cylinder
- 25mL measuring cylinder
- Filter funnels
- Oxygen gas
- Nitric Oxide gas
1. Fill both measuring cylinders completely with water. Carefully invert them over the trough so that the open end of each is at least 1cm below the surface of the water, and then clamp them in this position.
2. Place the pipe from the oxygen cylinder below the water surface, turn on the tap and bubble oxygen into the small cylinder until it contains about 5mLs of gas. Measure and record the volume of gas present.
3. Place the test tube of nitric oxide below the water surface. Using a submerged funnel, bubble the nitric oxide into the large measuring cylinder. Measure and record this volume.
4. Very carefully transfer the oxygen into the large measuring cylinder without allowing any to escape into the...