Identify the atoms in each of the following compounds which do not obey the octet rule:
`BeF_2`

Explanation

To determine which atoms in the compound beryllium difluoride (BeF₂) do not obey the octet rule, we can follow these steps:

### Step 1: Identify the valence electrons of each atom
- **Beryllium (Be)** has 2 valence electrons (it is in group 2 of the periodic table).
- **Fluorine (F)** has 7 valence electrons (it is in group 17 of the periodic table).

### Step 2: Determine the total number of electrons involved in bonding
In BeF₂, beryllium forms bonds with two fluorine atoms. Each fluorine atom will share one of its electrons with beryllium, resulting in the following:
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