Question

part c: types of reactions (5 marks)

chemical equation	type of reaction
2co₂o₃(s) → 4co(s) + 3o₂(g)
nicl₃ + 2kno₃ → 2kcl + ni(no₃)₃
2cu(s) + o₂(g) → 2cuo(s)

Explanation:

Step1: Analyze first equation

A single - element (Al) replaces another element (Cu) in a compound ($Cu(NO_3)_2$), so it's a single - replacement reaction.

Step2: Analyze second equation

A single compound ($Co_2O_3$) breaks down into two simpler substances (Co and $O_2$), so it's a decomposition reaction.

Step3: Analyze third equation

The positive ions ($Ni^{2 + },K^+$) and negative ions ($Cl^-,NO_3^-$) of two ionic compounds ($NiCl_2$ and $KNO_3$) exchange places, so it's a double - replacement reaction.

Step4: Analyze fourth equation

Two substances (Cu and $O_2$) combine to form a single compound ($CuO$), so it's a combination (synthesis) reaction.

Answer:

1. Single - replacement reaction
2. Decomposition reaction
3. Double - replacement reaction
4. Combination (synthesis) reaction