`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 need to analyze the reaction and determine the oxidation state of the central atom in the compound formed.

### Step 1: Identify the Reactants and Products
The reactants given are:
- NaCl (sodium chloride)
- K2Cr2O7 (potassium dichromate)
- Conc. H2SO4 (concentrated sulfuric acid)

When these reactants are warmed together, they produce reddish-brown fumes of a compound 'X'.

### Step 2: Determine the Product
The product formed from this reaction is CrO2Cl2, which is known as chromyl chloride. This is the compound 'X' that we need to analyze.

### Step 3: Identify the Central Atom
In the compound CrO2Cl2, the central atom is chromium (Cr).

### Step 4: Assign Oxidation States
To find the oxidation state of chromium in CrO2Cl2, we can set up an equation based on the known oxidation states of the other elements:
- Oxygen (O) typically has an oxidation state of -2.
- Chlorine (Cl) typically has an oxidation state of -1.

### Step 5: Set Up the Equation
Let the oxidation state of chromium be \( X \). The compound CrO2Cl2 can be expressed as:
\[ X + 2(-2) + 2(-1) = 0 \]

### Step 6: Simplify the Equation
Now, simplify the equation:
\[ X - 4 - 2 = 0 \]
\[ X - 6 = 0 \]

### Step 7: Solve for X
Solving for \( X \):
\[ X = +6 \]

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

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

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