Question

The linear molecule among the following is?
A.${H_2}S$
B.$C{l_2}O$
C.$Xe{F_2}$
D.$Cl{O_2}$

Answer 1

VSEPR theory proposes that the geometric arrangement of terminal atoms, or groups of atoms about a central atom in a covalent compound, or charged ion, is determined solely by the repulsions between electron pairs present in the valence shell of the central atom.

Complete Step by step answer: The main idea is that electrons don't like to hang around near each other because they repel each other. As a result, the atoms in a molecule tend to separate as far as they can because their bonds repel each other.
Linear molecule is a molecule in which atoms are deployed in a straight line (under 180 degree angle). Molecules with a linear electron pair geometries have sp hybridization at the central atom. The number of electron pairs are 2 that means the hybridization will be sp and the electronic geometry of the molecule will be linear.
${H_2}S$ molecule has an angular geometry because it has two lone pairs of electrons that make the molecule bend. The dipole moment is not zero. This is because sulphur is more electronegative than hydrogen, making the molecule slightly polar.
$Cl{O_2}$ and $C{l_2}O$ because the central oxygen atom has two lone electron pairs, it is classified as tetrahedral bent rather than trigonal planar bent. This geometric formation is characterized by bonding angles that are less than 109.5 degrees.
$Xe{F_2}$ molecular geometry is linear. It acquires such shape as the lone pairs present around the central atom tend to take up equatorial positions. The bond angle is said to be 180 degrees.

Hence the correct option is (c).

Note: The shape of a molecule depends upon the number of valence shell electron pairs around the central atom. And Pairs of electrons in valence shells repel one another since their electron clouds are negative.