When a mixture of solid `NaCl` and solid `K_(2)Cr_(2)O_(7)` is heated with concentrated `H_(2)SO_(4)` deep red vapours are obtained.This is due to the formation of:

Options

A. chromous chloride
B. chromyl chloride
C. chromic chloride
D. chromic sulphate

Answer

To solve the question regarding the formation of deep red vapors when a mixture of solid NaCl and solid K₂Cr₂O₇ is heated with concentrated H₂SO₄, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: The reactants in this case are solid sodium chloride (NaCl) and solid potassium dichromate (K₂Cr₂O₇), along with concentrated sulfuric acid (H₂SO₄).

2. **Understand the Reaction**: When NaCl is heated with K₂Cr₂O₇ and concentrated H₂SO₄, a chemical reaction occurs. The sulfuric acid acts as a dehydrating agent and facilitates the reaction between NaCl and K₂Cr₂O₇.

3. **Formation of Chromyl Chloride**: The reaction leads to the formation of chromyl chloride (CrO₂Cl₂), which is responsible for the deep red vapors observed. The balanced reaction can be summarized as:
\[ 2 \text{NaCl} + \text{K}_2\text{Cr}_2\text{O}_7 + 4 \text{H}_2\text{SO}_4 \rightarrow 2 \text{CrO}_2\text{Cl}_2 + 2 \text{Na}_2\text{SO}_4 + 2 \text{H}_2\text{O} + \text{K}_2\text{SO}_4 \]

4. **Observation of Deep Red Vapors**: The deep red vapors are specifically due to the presence of chromyl chloride (CrO₂Cl₂), which is known to produce a deep red color when vaporized.

5. **Conclusion**: Therefore, the formation of deep red vapors is due to the production of chromyl chloride when NaCl reacts with K₂Cr₂O₇ and concentrated H₂SO₄.

### Final Answer:
The deep red vapors obtained are due to the formation of **chromyl chloride (CrO₂Cl₂)**.

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