Find the oxidation number of:
Cr in `K_(2)Cr_(2)O_(7)`

Explanation

To find the oxidation number of chromium (Cr) in potassium dichromate, \( K_2Cr_2O_7 \), we can follow these steps:

### Step 1: Identify the oxidation states of the other elements
- The oxidation number of potassium (K) is +1.
- The oxidation number of oxygen (O) is -2.

### Step 2: Write the equation based on the compound
The formula for potassium dichromate is \( K_2Cr_2O_7 \). In this compound, there are:
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