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

Explanation

To find the oxidation number of iodine in potassium triiodide (KI₃), we can follow these steps:

### Step 1: Identify the oxidation state of potassium
Potassium (K) is an alkali metal and is located in Group 1 of the periodic table. The oxidation number for potassium is always +1.

### Step 2: Set up the equation for the oxidation numbers
In the compound KI₃, we have one potassium atom and three iodine atoms. Let the oxidation number of iodine be represented as \( X \). The overall charge of the compound is neutral (0), so we can set up the equation:

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