chemistry question

38.
Consider XeF4 .
AB4X2 , the 6 groups of electrons arranged in octahedral shape; the 2 lone pairs positioned in axial direction, yielding square planar molecule.

p.s. 3 is also wrong: consider BrF3 : an AB3X2
three lone pairs on equatorial plate, 2 bonds at axial direction.


100.
(s) = sigma MO, (p) = pi MO

O2 has 12 electrons in outermost shells

(2s)*
(2p)* ↑ ↑
(2p) ↑↓ ↑↓
(2s) ↑↓

(2s)* ↑↓
(2s) ↑↓


101.
I'm confused too..

B2 has 6 electrons:

(2s)*
(2p)*
(2p)
(2s) ↑↓

(2s)* ↑↓
(2s) ↑↓

unless you're talking about B2 (+) ion.