K₂Cr₂O₇ is heated with KCl in pressure of H₂SO₄. Find the correct match of product with their oxidation

Correct Answer: The correct option is CrO₂Cl₂, +6.

Step-by-Step Explanation:

1. Understanding the Reaction (Chromyl Chloride Test):
When potassium dichromate (K₂Cr₂O₇) is heated with a chloride salt such as potassium chloride (KCl) in the presence of concentrated sulfuric acid (H₂SO₄), a characteristic red-orange vapour of chromyl chloride (CrO₂Cl₂) is evolved.

The balanced chemical equation for this reaction is:

${\text{K}}_2{\text{Cr}}_2{\text{O}}_7+4\text{KCl}+6{\text{H}}_2{\text{SO}}_4\to 2{\text{CrO}}_2{\text{Cl}}_2+6{\text{KHSO}}_4+3{\text{H}}_2\text{O}$

2. Determining the Oxidation State of Chromium (Cr) in CrO₂Cl₂:
Let the oxidation state of chromium (Cr) be $x$.

We know standard oxidation states of the attached elements:
- Oxygen (O) typically has an oxidation state of -2.
- Chlorine (Cl) typically has an oxidation state of -1.

Set up the algebraic sum equation for the neutral molecule CrO₂Cl₂:

$x+2\times (-2)+2\times (-1)=0$

Simplifying the equation:

$x-4-2=0$

$x-6=0$

$x=+6$

Conclusion:
The product formed is CrO₂Cl₂ and the oxidation state of chromium in this compound is +6.