Certain organic compound on combustion produces three gaseous oxides A, B and C. A and C turned lime water milky, B turned anhydrous `CuSO_(4)` blue and C truned `K_(2)Cr_(2)O_(7)` solution green. The elements present in organic compounds are

Options

A. C, N, O
B. C, H, S
C. C, H only
D. C, S only

Answer

To solve the problem step by step, we need to analyze the information given about the combustion products A, B, and C, and determine the elements present in the organic compound.

### Step 1: Identify the compounds A, B, and C based on their reactions.

1. **A and C turned lime water milky**:
- Lime water (calcium hydroxide solution) turns milky when carbon dioxide (CO₂) is bubbled through it, forming calcium carbonate (CaCO₃).
- Sulfur dioxide (SO₂) can also react with lime water to form calcium sulfite (CaSO₃), which may also cause cloudiness.
- Therefore, A and C are likely to be CO₂ and SO₂.

2. **B turned anhydrous CuSO₄ blue**:
- Anhydrous copper sulfate (CuSO₄) is white and turns blue when it absorbs water (H₂O).
- Thus, B must be water (H₂O).

3. **C turned K₂Cr₂O₇ solution green**:
- Potassium dichromate (K₂Cr₂O₇) is orange in color and turns green when it is reduced, indicating that C is a reducing agent.
- The reducing agent that can reduce K₂Cr₂O₇ is likely to be SO₂, which is known to reduce chromium from +6 to +3 oxidation state, resulting in a green solution.

### Step 2: Confirm the identities of A, B, and C.

- **A**: CO₂ (carbon dioxide)
- **B**: H₂O (water)
- **C**: SO₂ (sulfur dioxide)

### Step 3: Identify the elements present in the organic compound.

From the identified compounds:
- **CO₂** contains carbon (C).
- **H₂O** contains hydrogen (H).
- **SO₂** contains sulfur (S).

### Conclusion

The elements present in the organic compound are carbon (C), hydrogen (H), and sulfur (S).

### Final Answer

The elements present in the organic compounds are C, H, and S.

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