Give two examples for Physical changes which are not reversible .

Explanation

To answer the question about providing two examples of physical changes that are not reversible, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Physical Changes**:
- A physical change is a change that does not alter the chemical composition of a substance. This means that the substance remains the same at a molecular level, and no new substances are formed.

**Hint**: Remember that in physical changes, the original substance can often be recovered, but we are looking for examples where this is not possible.
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