Activity 1E (Textbook) – Chemistry Form 5 Chapter 1 (Redox Equilibrium)

Carry out this activity in pairs.
Record the findings in your notebook.
Question 1:
State the name of the following compounds according to the IUPAC nomenclature.
(a) Cu₂O
(b) CuO
(c) Hg₂Cl₂
(d) HgCl₂
(e) K₂CrO₄

Answer:
(a) Copper(I) oxide

(b) Copper(II) oxide

(c) Mercury(I) chloride

(d) Mercury(II) chloride

(e) Potassium chromate(VI)

Question 2:
Write the formula for the following compounds.
(a) Vanadium(V) oxide
(b) Sodium oxide
(c) Lead(II) carbonate

Answer:
(a) V₂O₅
(b) Na₂O
(c) PbCO₃

Question 3:
State the name of the following two compounds according to the IUPAC nomenclature and explain the reason for the difference of those names.

Answer:
Fe₂O₃ : Iron(III) oxide
Al₂O₃ : Aluminium oxide

– The nomenclature of compound Fe₂O₃ has a Roman numeral, while Al₂O₃ does not have a Roman numeral.

– Iron has more than one oxidation number and the Roman numeral of iron(III) oxide shows the oxidation number of iron is +3, while aluminium has only one oxidation number and does not need a Roman numeral.