1.1. This question is about oxidation numbers.

Complete Table 1 giving the oxidation number of sulfur in the following compounds.

Table 1

1.2. State the oxidation number of sulfur in its elemental form of S₈. 

1.3. The reaction between tin chloride and magnesium is classed as a redox reaction

SnCl₄ + 2Mg → 2MgCl₂ + Sn 

i) State the change in oxidation number of magnesium.

[1] 

ii) State the change in oxidation number of tin.

[1] 

iii) Deduce which species is acting as the reducing agent.

[1]

1.4. Antimony reacts with nitric acid to form antimony oxide, nitrogen monoxide and water as shown the following equation.

Sb + HNO₃ → Sb₂O₃ + NO + H₂O

i) State the change in oxidation number of antimony.

[1]

ii) State the change in oxidation number of nitrogen.

[1]

iii) Identify the oxidising agent in this reaction.

[1]