Question

Use VSEPR theory to predict the shape of each of the following:
a. ${\mathrm{GaH}}_3$
b. ${\mathrm{OF}}_2$
c. $\mathrm{HCN}$
d. ${\mathrm{CCl}}_4$

Short answer

Part(a) ${\mathrm{GaH}}_3$has trigonal planar shape.

Part(b) ${\mathrm{OF}}_2$has Bent shape.

Part(c) $\mathrm{HCN}$has linear shape.

Part(d) ${\mathrm{CCl}}_4$has tetrahedral shape.

Step-by-step solution

Part(a) Step 1 : Given information

We are given some compounds to predict the shape using VSEPR theory.

Part(a) Step 2 : Simplify

According to VSEPR theory ${\mathrm{GaH}}_3$has a trigonal planar structure.

Part(b) Step 1 : Given information

We are given some compounds to predict the shape using VSEPR theory.

Part(b) Step 2 : Simplify

${\mathrm{OF}}_2$ has a linear geometry, according to the VSEPR theory.
The lone pair repulsion of oxygen and fluorine electrons causes the linear geometry.
The molecular configuration of oxygen difluoride is similar to that of water, and lone pair repulsion causes it to bend.
Due to fluorine's high lone pair repulsion, the bond angle is somewhat greater than the angle between hydrogen atoms in water.
As a result, we can state that ${\mathrm{OF}}_2$ has a tetrahedral electron geometry and a linear molecular geometry.

Part(c) Step 1 : Given information

We are given some compounds to predict the shape using VSEPR theory.

Part(c) Step 2 : Simplify

According to the VSEPR theory, the $\mathrm{HCN}$ molecule ion has a linear molecular geometry.
Because the carbon atom in the centre is connected to the hydrogen atoms around it by a single $\mathrm{H}-\mathrm{CN}$ bond.
The $\mathrm{H}-\mathrm{CN}$bond angle is $180$ degrees in linear geometry.
The $\mathrm{HCN}$molecule has a linear molecular geometry shape because it has one hydrogen atom in one terminal and another nitrogen atom in the opposite terminal, each with one lone pair of electrons.

Part(d) Step 1 : Given information

We are given some compounds to predict the shape using VSEPR theory.

Part(d) Step 2 : Simplify

According to the VSEPR model, the electron zones around an atom expand out to make each region as far apart as possible.
These ${\mathrm{CCl}}_4$ clouds will point toward the corners of a tetrahedron in order to be as far apart as feasible.
The bonds will emerge from the centre atom at $109.5°$ angles to one another.
Tetrahedral structure will be used.