`H_(2)S` gas can be obtained by the action of water on:

Options

A. `CuS`
B. `FeS`
C. Flower of sulphur
D. `Al_(2)S_(3)`

Answer

To determine which compound can produce hydrogen sulfide (H₂S) gas when reacted with water, we will analyze the given options step by step.

### Step 1: Identify the Compounds
We need to look at the compounds provided in the options. The question specifically asks for a compound that will react with water to produce H₂S.

### Step 2: Analyze the Reaction
We know that certain metal sulfides can react with water to produce hydrogen sulfide gas. One common example is aluminum sulfide (Al₂S₃).

### Step 3: Write the Reaction
When aluminum sulfide reacts with water, the reaction can be represented as follows:

\[ \text{Al}_2\text{S}_3 + 6 \text{H}_2\text{O} \rightarrow 2 \text{Al(OH)}_3 + 3 \text{H}_2\text{S} \]

In this reaction, aluminum sulfide reacts with water to produce aluminum hydroxide and hydrogen sulfide gas.

### Step 4: Conclusion
Based on the reaction above, we can conclude that the compound that can produce H₂S gas when reacted with water is aluminum sulfide (Al₂S₃).

### Final Answer
The correct answer is **Al₂S₃**.

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