`NaCl(solid)+K_(2)Cr_(2)O_(7)(solid)+conc.H_(2)SO_(4) overset(warm)to`Reddish brown fumes of 'X'.
The oxidation state of central atom in compound 'X' is:

Options

A. `+6`
B. `+3`
C. `+2`
D. zero

Explanation

To solve the problem step by step, we will analyze the reaction and determine the oxidation state of the central atom in the compound formed.

### Step 1: Identify the reactants and the product
The reactants given are:
- NaCl (solid)
- K₂Cr₂O₇ (solid)
- Concentrated H₂SO₄ (warm condition)

When these reactants are combined, they produce reddish-brown fumes of a compound, which we need to identify.

### Step 2: Determine the product formed
The reaction of NaCl with K₂Cr₂O₇ and concentrated H₂SO₄ leads to the formation of chromyl chloride, which is represented as CrO₂Cl₂. This compound is responsible for the reddish-brown fumes observed during the reaction.

### Step 3: Write the chemical formula of the product
The product formed is chromyl chloride, which has the chemical formula CrO₂Cl₂.

### Step 4: Assign oxidation states to the elements in the product
To find the oxidation state of chromium (the central atom) in CrO₂Cl₂, we can assign oxidation states as follows:
- Oxygen (O) has an oxidation state of -2.
- Chlorine (Cl) has an oxidation state of -1.

### Step 5: Set up the equation for the oxidation state
Let the oxidation state of chromium (Cr) be represented as \( x \). The overall charge of the compound CrO₂Cl₂ is neutral (0). Therefore, we can set up the equation based on the oxidation states:

\[ x + 2(-2) + 2(-1) = 0 \]

### Step 6: Solve for the oxidation state of chromium
Now, simplify the equation:

\[ x - 4 - 2 = 0 \]
\[ x - 6 = 0 \]
\[ x = +6 \]

### Conclusion
The oxidation state of the central atom (chromium) in the compound CrO₂Cl₂ (chromyl chloride) is +6.

### Final Answer
The oxidation state of the central atom in compound 'X' (CrO₂Cl₂) is +6.

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