What is the oxidation number of iodine in `Kl_(3)`?

Answer

To find the oxidation number of iodine in the compound \( KI_3 \), we can follow these steps:

### Step 1: Identify the components of the compound
In the compound \( KI_3 \), we have potassium (K) and iodine (I). Potassium is an alkali metal and typically has an oxidation number of +1.

### Step 2: Set up the equation for oxidation numbers
Let the oxidation number of iodine be \( x \). Since there are three iodine atoms in \( KI_3 \), the total contribution from iodine will be \( 3x \).

### Step 3: Write the charge balance equation
The overall charge of the compound \( KI_3 \) is neutral (0). Therefore, we can set up the following equation based on the oxidation numbers:
\[ \text{Oxidation number of K} + \text{Oxidation number of I} = 0 \]
Substituting the known values:
\[ +1 + 3x = 0 \]

### Step 4: Solve for \( x \)
Now, we can solve for \( x \):
\[ 3x = -1 \]
\[ x = -\frac{1}{3} \]

### Conclusion
The oxidation number of iodine in \( KI_3 \) is \( -\frac{1}{3} \).

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