Topic 7 Oxygen and Sulphur Compounds

The following are properties of oxygen except for

• It is linear shape molecule.

• It can form ionic compounds by accepting 2 electrons.

• It has sharp irritating odour.

• It is neutral.

The following are basic oxides except for

• CuO

• BaO

• Rb₂O

• BeO

The following are the properties of ozone except for

• It is a pale blue gas

• It is a strong reducing agent

• It is a polar molecule

• It is unstable

The following are the uses of ozone except for

• It is important for human respiration

• Decontaminate operating rooms between surgeries

• Detoxify cyanide waste

• Bleaching of wood pulp

Which of the following is not true about sulphur?

• It cannot conduct electricity.

• It is soluble in water.

• It is in the solid state of S₈ at room temperature.

• It burns with blue flame and emit SO₂ gas.

Which of the following is not true about sulphur dioxide, SO₂?

• SO₂ can act as an oxidising agent.

• SO₂ can act as a reducing agent.

• SO₂ is released in the combustion of fossil fuels.

• SO₂ is a basic gas.

The following equation shows one of the reactions occurring in the Contact process:

2SO_2(g) + O_2(g) <---> 2SO_3(g) ∆H = –198 kJ mol^-1

The yield of SO₃ can be increased by:

• Removing some SO₃ as it forms.

• Adding more catalyst.

• Increasing the temperature.

• Decreasing the pressure.

Choose the correct sequence for the Frasch process.

I. Compressed air is pumped down the center tube.

II. Sulfur slurry is forced out from the middle tube.

III. Superheated steam is forced down the outer tube.

• I, II, III

• III, I, II

• III, II, I

• II, III, I

The following are properties of sulphuric acid except for

• It is a diprotic acid

• It turns blue litmus paper to red

• It reacts with metal to form salt and water

• salt of H₂SO₄ can be identified by adding acidified barium chloride solution

SO₃ is not allowed to react with H₂O directly because

• The reaction is highly endothermic

• The reaction is slow

• The acid produced is diluted

• The reaction is violent and creates fog of H₂SO₄