The oxidation state of `Cr` in `Potassium Dichromate` is:
(a)`+5`
(b)`+3`
(c)`+6`
(d)`+7`

Options

A. `+5`
B. `+3`
C. `+6`
D. `+7`

Explanation

To determine the oxidation state of chromium (Cr) in potassium dichromate (K₂Cr₂O₇), we can follow these steps:

### Step 1: Write the formula for potassium dichromate
The chemical formula for potassium dichromate is K₂Cr₂O₇.

### Step 2: Assign oxidation states to known elements
- Potassium (K) has an oxidation state of +1.
- Oxygen (O) has an oxidation state of -2.

### Step 3: Set up the equation based on the overall charge
Since potassium dichromate is a neutral compound, the sum of the oxidation states must equal zero. We can express this as:
\[ 2 \times (\text{oxidation state of K}) + 2 \times (\text{oxidation state of Cr}) + 7 \times (\text{oxidation state of O}) = 0 \]

Substituting the known oxidation states:
\[ 2 \times (+1) + 2 \times x + 7 \times (-2) = 0 \]

### Step 4: Simplify the equation
Now, we can simplify the equation:
\[ 2 + 2x - 14 = 0 \]

### Step 5: Solve for x
Rearranging the equation:
\[ 2x - 12 = 0 \]
\[ 2x = 12 \]
\[ x = 6 \]

### Conclusion
The oxidation state of chromium (Cr) in potassium dichromate (K₂Cr₂O₇) is +6.

### Answer
(c) +6

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