Except for lithium, alkali metals form their hydrides at what temperature.

Explanation

To solve the question of at what temperature alkali metals (except lithium) form their hydrides, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Alkali Metals and Hydrides**:
- Alkali metals include lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr).
- These metals can react with dihydrogen (H₂) to form hydrides.

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