Some word/words are missing/written wrong in the following statement. You are required to rewrite the statement in the correct form using the appropriate word/words
When `MnO_2` is heated with conc. HCI, a greenish-yellow, hydrogen gas, is produced.

Explanation

To rewrite the statement correctly, we need to identify and correct the errors in the original statement. Here’s the step-by-step solution:

1. **Identify the Reactants**: The original statement mentions `MnO2` and `conc. HCl`. These are the correct reactants for the reaction.

2. **Identify the Product**: The original statement incorrectly states that "hydrogen gas" is produced. However, upon examining the reaction, we find that the actual products are manganese(II) chloride (MnCl2), water (H2O), and chlorine gas (Cl2).

3. **Determine the Color of the Gas**: The statement mentions a "greenish-yellow" gas. This description is accurate for chlorine gas (Cl2), which is indeed a greenish-yellow gas.

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