Question

Which statement is correct about $IC{l_3}$ molecules?
A. All $I - Cl$ bonds are equivalent.
B. Molecules are polar and nonplanar.
C. All adjacent bond angles are equal.
D. All hybrid orbitals of the central atom having equal s- character.

Answer 1

In order to answer this question, we should know about the structure of the molecule given which is $IC{l_3}$ . We should know how the atoms are bonded within a molecule. For this, we should know about the valence electrons of the atom present in a molecule.

Complete answer:
Let us understand this question in complete detail.
First, let's see the structure of $IC{l_3}$ molecules.
The chemical name of the $IC{l_3}$ molecule is Iodine trichloride. It is an interhalogen compound made up of iodine and chlorine.
Iodine has seven electrons and each chlorine provides one electron giving a total of five pairs.
These five pairs of electrons arrange themselves and form trigonal bipyramidal. According to valence shell electron pair repulsion (VSEPR) theory, T-shape is expected to form for iodine trichloride but the original shape is trigonal bipyramidal.
The molecule $IC{l_3}$ is polar and non-planar because its net dipole moment is not equal to zero due to the difference between the electronegativity of iodine and chlorine. So, option (B) is not correct.
Also, all $I - Cl$ bonds are not equivalent. Some are equivalent or some are axial bonds. So, option (A) is not correct.
Equatorial $I - Cl$ bond has more s-character than axial $I - Cl$ bonds. So, option (D) is not correct.
All the adjacent bond angles are equal in $IC{l_3}$ molecules.
Hence, option (C) is correct.

Note:
It must be remembered as an additional information that interhalogen compounds are very reactive and less stable than halogens. The reason is that the covalent bonds are stronger than ionic bonds.