Borate from green colour flame when burnt with (Conc. `H_2SO_4+` ethanol). Green colour flame is obtained due to due to formation of

Options

A. `(C_2H_5O)_3B`
B. `(C_2H_5)_2BO_3`
C. `(C_2H_5)_3B`
D. A and C are correct

Answer

To solve the question regarding the formation of a green color flame when borate is burnt with concentrated sulfuric acid (H₂SO₄) and ethanol, we can break down the process into several steps.

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactants in this reaction are borate (specifically borax, Na₂B₄O₇), concentrated sulfuric acid (H₂SO₄), and ethanol (C₂H₅OH).

**Hint**: Look for the components that are involved in the reaction and their chemical formulas.

2. **Understand the Reaction**:
- When borax is heated with concentrated H₂SO₄, it undergoes a chemical reaction. The sulfuric acid reacts with borax to produce sodium sulfate (Na₂SO₄) and boric acid (H₃BO₃).

**Hint**: Consider the products formed when acids react with borates.

3. **Formation of Triethyl Borate**:
- The boric acid (H₃BO₃) then reacts with ethanol (C₂H₅OH) to form triethyl borate (C₂H₅O)₃B and water (H₂O). The reaction can be represented as:
\[ H₃BO₃ + 3C₂H₅OH \rightarrow (C₂H₅O)₃B + 3H₂O \]

**Hint**: Recognize the reaction between boric acid and alcohol to form an ester.

4. **Color of the Flame**:
- The green color of the flame is attributed to the presence of triethyl borate. When it is burned, it emits a green flame due to the boron compounds present in the reaction.

**Hint**: Think about how different compounds can affect the color of flames when burned.

5. **Conclusion**:
- Therefore, the green color flame is obtained due to the formation of triethyl borate (C₂H₅O)₃B.

**Hint**: Summarize the findings to arrive at the final answer.

### Final Answer:
The green color flame is obtained due to the formation of triethyl borate, represented as (C₂H₅O)₃B.