`"Colemanite" + Na_(2)CO_(3) overset("Fused")rarr (A) + (B) + CO_(2)`
`underset("Solution")((A)) + CO_(2) rarr(B) + Na_(2) CO_(3)`
`(B) + conc HCl rarr NaCl + underset("Acid")((C))`
`underset("Acid")((C)) +H_(2)O rarr underset("Acid")((D))`
`(D) overset("Strong heating")rarr (E)`
`(E) +CuSO_(4) overset("Heated") underset("inflame")rarr underset("Blue-coloured compound")((F))`.
Compound `(C)` is.

Options

A. `H_(2)B_(4)O_(7)`
B. `HBO_(2)`
C. `H_(3)BO_(3)`
D. `H_(2)O`

Explanation

To solve the question step by step, we will analyze the reactions provided and identify the compounds involved.

### Step 1: Identify the reaction of Colemanite with Na₂CO₃
- **Reaction**: Colemanite (Ca₂B₆O₁₁) is fused with sodium carbonate (Na₂CO₃).
- **Products**: The products of this reaction are sodium metaborate (A) and another compound (B), along with carbon dioxide (CO₂).

**Equation**:
Ca₂B₆O₁₁ + Na₂CO₃ (fused) → NaBO₂ (A) + B + CO₂

### Step 2: Identify compound B
- **Next Reaction**: Sodium metaborate (A) reacts with CO₂ to produce compound B and regenerate sodium carbonate.

**Equation**:
NaBO₂ + CO₂ → Na₂B₄O₇ (B) + Na₂CO₃

### Step 3: Identify compound C
- **Next Reaction**: Compound B (Na₂B₄O₇) reacts with concentrated HCl.

**Equation**:
Na₂B₄O₇ + HCl (conc.) → NaCl + H₂B₄O₇ (C)

### Step 4: Identify compound D
- **Next Reaction**: The acid (C) reacts with water (H₂O).

**Equation**:
H₂B₄O₇ + H₂O → H₃BO₃ (D)

### Step 5: Identify compound E
- **Next Reaction**: Compound D is subjected to strong heating.

**Equation**:
H₃BO₃ (D) (strong heating) → B₂O₃ (E)

### Step 6: Identify compound F
- **Next Reaction**: Compound E reacts with CuSO₄ when heated to produce a blue-colored compound.

**Equation**:
B₂O₃ + CuSO₄ (heated) → CuB₂O₄ (F) (blue-colored compound)

### Conclusion
- The compound C identified in the reaction sequence is **H₂B₄O₇**.

### Final Answer
**Compound (C) is H₂B₄O₇.**

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