Camphor pellets should be preserved in air-tight containers. Give reasons.

Explanation

### Step-by-Step Solution:

1. **Understanding Camphor**: Camphor is a solid substance that is commonly used for its aromatic properties and is often found in the form of pellets.

2. **Sublimation Process**: Camphor undergoes a process known as sublimation. This is when a solid turns directly into vapor without passing through the liquid state.

3. **Conditions for Sublimation**: Sublimation occurs at atmospheric pressure, meaning that under normal conditions, camphor can easily change from solid to gas.

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