Two materials A and B are heated separately in air. The product formed is dissolved in water. How will you identify which one is a metal?

Explanation

To identify which of the two materials, A or B, is a metal based on the products formed when they are heated in air and subsequently dissolved in water, follow these steps:

### Step-by-Step Solution:

1. **Heating the Materials**:
- Heat material A in air. This will lead to the formation of an oxide of A (let's call it Oxide A).
- Heat material B in air. This will lead to the formation of an oxide of B (let's call it Oxide B).

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