On a separate sheet of paper, write the formulas for each of the following, complete and balance

1. iron + copper (II) sulfate

2. potassium chloride + mercury (I) sulfate

3. sulfur + oxygen

Answer: The first reaction is a single replacement reaction

Fe + CuSO4 = > FeSO4 + Cu

Note the charges are indicated in the chemical reaction. SO4 is - 2, so Fe is 2 + same with copper

2. Is a double replacement reaction

KCl + Hg2SO4 = > K2SO4 + HgCl

Balance then chemical reaction

2 KCl + Hg2SO4 = > K2SO4 + 2HgCl

K has a + 1 oxidation, Cl is - 1, Hg is + 1, SO4 has a - 2 oxidation

3. Is a synthesis reaction

S + O2 = > SO2

The answer to your question is below

Explanation:

1. iron + copper (II) sulfate ⇒ Iron sulfate + copper

Fe + CuSO₄ ⇒ FeSO₄ + Cu

This is a single replacement reaction

2. potassium chloride + mercury (I) sulfate ⇒ potassium sulfate + mercury (I) chloride

2KCl + Hg₂SO₄ ⇒ K₂SO₄ + 2HgCl

This is a double replacement reaction

3. Sulfur + oxygen ⇒ sulfur dioxide

S + O₂ ⇒ SO₂

This is a synthesis reaction

Now, all the reactions are balanced.