The elements shown are gases at room temperature and pressure.
- hydrogen
- nitrogen
- oxygen
- chlorine
(a) State which one of these gases is green.
(b) The gases shown exist as diatomic molecules.
State the name of another element which has diatomic molecules and is a gas at room temperature and pressure.
(c) When separate samples of each of these gases are placed in a container they will diffuse.
(i) Describe why these gases diffuse.
(ii) State which of these four gases has the highest rate of diffusion.
Explain your answer.
(d) Nitrogen, oxygen and other substances are found in clean, dry air.
(i) State the percentage of nitrogen in clean, dry air.
(ii) Other than nitrogen and oxygen, identify another element found in clean, dry air.
(iii) Identify a compound found in clean, dry air.
(iv) Nitrogen and oxygen can be separated from liquid air.
State the name of this process.
