KrF2 (krypton difluoride) is a nonpolar molecule. Because the molecule has a symmetrical geometry. The two identical bond dipoles pull in perfectly opposite directions, they cancel each other out, resulting in no net dipole moment.

Step 1: Calculation of total valence electrons

Kr (Krypton, noble gas): valence electrons = 8

F (Fluorine): 7 × 2 = 14

Total valence electrons: 8 + 14 = 22

Step 2: Determination of bonding skeleton

Kr is the central atom (lower electronegativity, capable of an expanded octet)

Connectivity: F?Kr?F, linear skeleton

Step 3: Form σ bonds

F?Kr?F (two single bonds), electrons used: 2 × 2 = 4 e?

Remaining electrons: 22 ? 4 = 18 e?

Step 4: Satisfy the octets of the peripheral F atoms 

Each F requires 6 lone electrons (3 pairs)

Total lone electrons for 2 F atoms: 2 × 6 = 12 e?

Remaining electrons after allocation: 18 ? 12 = 6 e?

Step 5: Place all remaining electrons on the central Kr atom

6 e? = 3 lone pairs located on the Kr atom

Since Kr is a Period 4 noble gas with empty d-orbitals, it can accommodate an expanded octet

Kr bonding electrons: 2 (two single bonds) + 6 (lone pairs) = 10 electrons; this is permissible.