In what ways lithium shows similarities to magnesium in its chemical behaviour?

Explanation

To understand the similarities in chemical behavior between lithium and magnesium, we can break down the information into specific points of comparison:

### Step-by-Step Solution:

1. **Oxide Solubility**:
- Both lithium oxide (Li2O) and magnesium oxide (MgO) are less soluble in water compared to other oxides of their respective groups. This means that when they are added to water, they do not dissolve easily.

2. **Hydroxide Decomposition**:
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