Small pieces of steel and some powdered rust are taken in two test tubes separately. What will you obseve when concentrated hydrochloric acid is poured into both the test tubes ? Justify your observation.

Explanation

### Step-by-Step Solution:

1. **Identify the Materials**: We have two test tubes. One contains small pieces of steel and the other contains powdered rust (iron oxide).

2. **Add Concentrated Hydrochloric Acid**: We will pour concentrated hydrochloric acid (HCl) into both test tubes.

3. **Observation with Steel**:
- When concentrated hydrochloric acid is added to the small pieces of steel, a chemical reaction occurs.
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