Which of the following statements indicates that law of multiple proportion is being followed.
1
Sample of carbon dioxide taken from any source will always have carbon and oxygen in the ratio 1 ∶ 2.
2
Carbon forms two oxides namely CO2 and CO, where masses of oxygen which combine with fixed mass of carbon are in the simple ratio 2 ∶ 1.
3
When magnesium burns in oxygen, the amount of magnesium taken for the reaction is equal to the amount of magnesium in magnesium oxide formed.
4
At constant temperature and pressure 200 mL of hydrogen will combine with 100 mL oxygen to produce 200 mL of water vapour.