`IF_(7)` exists but `BrF_(7)` does not, why ?

Explanation

To understand why IF₇ exists but BrF₇ does not, we need to consider the following factors:

### Step 1: Analyze the central atom
- **Iodine (I)** and **Bromine (Br)** are both halogens and can expand their octet. However, iodine is larger than bromine.

### Step 2: Consider the size of the central atom
- The size of iodine is larger than that of bromine. This larger size allows iodine to accommodate more fluorine atoms around it without significant electron-electron repulsion.

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