Question

Match the interhalogen compounds of column I with the geometry in column II and assign the correct code.

Column I	Column II
a. ${{XX}^{\text{'}}}$	i. T-shape
b. ${XX_3}^{\text{'}}$	ii. Pentagonal bipyramidal
c. ${XX_5}^{\text{'}}$	iii. Linear
d. ${XX_7}^{\text{'}}$	iv. Square-pyramidal
v. Tetrahedral

A) (a)-iv, (b)-iii, (c)-ii, (d)-i
B) (a)-iii, (b)-iv, (c)-i, (d)-ii
C) (a)-iii, (b)-i, (c)-iv, (d)-ii
D) (a)-v, (b)-iv, (c)-iii, (d)-ii

Answer 1

We know that the interhalogen compounds are those which have central metal as halogen and the metal attached to it is also halogen. The structure is based on the VSEPR Theory.

Complete answer:
The bond angle is the angle between the two atoms bonded to the central atom. It is dependent on the non-bonded pairs and the bonded pair.
As per the VSEPR theory of the atom, the strength of the repulsion between a lone pair and a bond pair of electrons lies in between the repulsion between two lone pairs and between two bond pairs. The order of repulsion between electron pairs as follows:
Lone Pair- lone pair $>$ Lone Pair- bond- pair $>$ Bond Pair- bond pair.
The hybridization and non-bonding electron pairs will decide the shape of the molecule and structure of the molecule.
The central metal atom in interhalogen will have seven electrons in the valence shell. Central metal will form a bond with another halogen when that halogen will be sharing one electron to the central halogen atom, central metal, and metal surrounding it will complete the octet state by forming a covalent bond. There is a possibility that the unpaired electron pair will remain free and surround the central metal which will affect the bond angles.
(a) ${{XX}^{\text{'}}}$will have linear geometry as it has only two atoms and the hybridization will be $sp$. Matches with (iii).
(b) ${XX_3}^{\text{'}}$ will have T-shaped geometry as $3$ bond pairs and $2$lone pairs of electrons are present. The electron pair geometry is trigonal bipyramidal. Matches with (i).
(c) ${XX_5}^{\text{'}}$ has Square - pyramidal geometry as 5 bond pairs and 1 lone pair of electrons are present. The electron pair geometry is octahedral. Matches with (iv).
(d) ${XX_7}^{\text{'}}$ has pentagonal bipyramidal geometry as 7 bond pairs and 0 lone pairs of electrons are present. Matches with (ii).

**Hence, the correct option is (C) (a)-iii, (b)-i, (c)-iv, (d)-ii.

Note: **
For tetrahedral shape the hybridization is $s{p^3}$ and the angle is ${109.5^ \circ }$, if non-bonding pairs are present, then the angle will be less than ${109.5^ \circ }$.