What happens when (a) magensium in burnt in air, (b) quicklime is heated with silica, (c ) chlorine reacts with slaked lime and (d) calcium nitrate is heated?

Explanation

Let's break down the question step by step.

### Step 1: Magnesium is burnt in air
When magnesium (Mg) is burnt in air, it reacts with oxygen (O2) and nitrogen (N2) present in the air. The two main products formed are magnesium oxide (MgO) and magnesium nitride (Mg3N2).

**Reactions:**
1. Formation of magnesium oxide:
\[
...