What are the oxidation number of the underlined elements in each of the following and how do you rationalise your results?
`ul(Fe)_(3)O_(4)`

Explanation

To determine the oxidation number of iron (Fe) in the compound Fe₃O₄, we can follow these steps:

### Step 1: Write the formula and assign oxidation states
The compound given is Fe₃O₄. We need to find the oxidation number of iron (Fe). Let's denote the oxidation number of iron as \( x \).

### Step 2: Assign the oxidation number of oxygen
We know that the oxidation number of oxygen (O) in most compounds is -2. Since there are 4 oxygen atoms in Fe₃O₄, the total contribution from oxygen will be:
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