1.1. This question is about oxidation numbers.

Complete Table 1.1 to show the oxidation number of sulfur in each compound.

Table 1.1

1.2. State the oxidation number of sulfur in S₈.

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

SnCl₄ (l) + 2Mg (s) → 2MgCl₂ (s) + Sn (s)

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(III) oxide, nitrogen monoxide and water as shown in the following equation.

2Sb (s) + 2HNO₃ (aq) → Sb₂O₃ (s) + 2NO (g) + H₂O (l)

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]