Which gas is released when a metal reacts with an acid ?

Options

A. `Cl_(2)`
B. `O_(2)`
C. `H_(2)`
D. `SO_(2)`

Answer

**Step-by-Step Solution:**

1. **Understanding the Reaction**: When a metal reacts with an acid, a chemical reaction occurs. This reaction typically produces a salt and hydrogen gas.

2. **Identifying the Components**: In this reaction, the metal is the reactant that combines with the acid. The acid provides hydrogen ions (H⁺) that will ultimately form hydrogen gas (H₂).

3. **General Reaction Formula**: The general formula for the reaction between a metal (M) and an acid (HA) can be represented as:
\[ M + HA \rightarrow MA + H_2 \]
Here, MA is the salt formed from the metal and the acid.

4. **Example Reaction**: For instance, if we take sodium (Na) as the metal and hydrochloric acid (HCl) as the acid, the reaction can be written as:
\[ 2 \text{Na} + 2 \text{HCl} \rightarrow 2 \text{NaCl} + \text{H}_2 \]
In this reaction, sodium chloride (NaCl) is the salt produced, and hydrogen gas (H₂) is released.

5. **Conclusion**: Therefore, the gas released when a metal reacts with an acid is hydrogen gas (H₂).

**Final Answer**: Hydrogen gas (H₂) is released when a metal reacts with an acid.

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