The sum of lone pairs present on the central atom of the interhalogen IF$$_5$$ and IF$$_7$$ is _______.

IF₅: Iodine has 7 valence electrons. With 5 F atoms bonded, the structure is square pyramidal.

Total electron pairs around I = 5 bond pairs + 1 lone pair = 6 (sp³d² hybridization).

Lone pairs on central atom = 1.

IF₇: Iodine has 7 valence electrons. With 7 F atoms bonded, the structure is pentagonal bipyramidal.

Total electron pairs around I = 7 bond pairs + 0 lone pairs (sp³d³ hybridization).

Lone pairs on central atom = 0.

Sum of lone pairs = 1 + 0 = 1.