X is an element in the form of a powder. X burns in oxygen and the product is soluble in water. The solution is tested with litmus. Write down only the word, which will correctly complete the following sentence.
If X is a reactive metal, then ____ will be evolved, when X reacts with dilute sulphuric acid.

Explanation

To solve the question, we need to analyze the information provided about element X and its reactions.

1. **Identify Element X**:
- X is described as a powder that burns in oxygen, producing a product that is soluble in water.
- The product is tested with litmus, indicating it is likely an acidic or basic solution.

2. **Determine the Reaction with Dilute Sulfuric Acid**:
- Since X is a reactive metal, when it reacts with dilute sulfuric acid (H₂SO₄), it will undergo a chemical reaction.
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