Question

Give the number of lone pairs in the central atoms of the following inter halogen compounds $AX$, $A{X}_3$, $A{X}_5$, $A{X}_7$.

• A. 3, 2, 1, 1
• B. 3, 2, 1, 0
• C. 3, 1, 2, 0
• D. 3, 2, 2, 0

Answer 1

Answer: (B)

3, 2, 1, 0

An interhalogen compound is a molecule that contains two or more different halogen atoms (fluorine, chlorine, bromine, iodine, or astatine) and no atoms of elements from any other group.

Halogens have a maximum valency of 7.

Thus, number of lone pairs in:

$AX=:\stackrel{..}{\underset{..}{A}}-X=3$

$A{X}_3=X-\stackrel{....}{\underset{X}{A}}-X=2$

$A{X}_5=X-\stackrel{..}{\underset{XXX}{A}}-X=1$

$A{X}_7=X-\stackrel{XX}{\underset{XXX}{A}}-X=0$

Option B is correct.