Q. 6.144 - An Introduction to General, Organic, and Biological Chemistry

Question

Classify each of the following molecules as polar or non-polar. 

a. ${\mathrm{GeH}}_2$

b. ${\mathrm{I}}_2$

c. ${\mathrm{CF}}_3\mathrm{Cl}$

d. ${\mathrm{PCl}}_5$${\mathrm{PCl}}_5$

e. ${\mathrm{BCl}}_3$

f. ${\mathrm{SCl}}_2$

Step-by-Step Solution

Answer

a. Non-polar molecule.

b. Non-polar molecule. 

c. Polar molecule.

d. Non-polar molecule.

e. Polar molecule.

f. Polar molecule.

Step 1: Part (a) Given information

To determine whether ${\mathrm{GeH}}_2$ is a polar or non-polar molecule.

Step 2: Part (a) Explanation

${\mathrm{GeH}}_2$ is a non-polar molecule due to the equal sharing of electrons between the atoms.

A non-polar covalent bond is a bond that is formed when electrons are shared equally between two atoms. 

Step 1: Part (b) Given Information

To determine whether ${\mathrm{I}}_2$ is a polar or non-polar molecule.

Step 2: Part (b) Explanation

Iodine has a linear geometry and it is a symmetrical molecule.

It is a non-polar molecule due to the equal sharing of electrons between the atoms.

A non-polar covalent bond is a bond that is formed when electrons are shared equally between two atoms.

Step 1: Part (c) Given Information

To determine whether ${\mathrm{CF}}_3\mathrm{Cl}$ is a polar or non-polar molecule.

Step 2: Part (c) Explanation

${\mathrm{CF}}_3\mathrm{Cl}$ is composed of Carbon, Fluorine, and chlorine atoms.

It has a  tetrahedral geometry and due to the difference between the electronegativity of C, Cl, and, F, it is a polar molecule.

Step 1: Part (d) Given information

To determine whether ${\mathrm{PCl}}_5$ is a polar or non-polar molecule.

Step 2: Part (e) Explanation

Phosphorus pentachloride has a trigonal bipyramidal geometry. 

A non-polar covalent bond is a bond that is formed when electrons are shared equally between two atoms 

The dipoles present in ${\mathrm{PCl}}_5$ cancel each other, making the molecule non-polar.

Step 1: Part (e) Given Information

To determine whether ${\mathrm{BCl}}_3$ is a polar or non-polar molecule.

Step 2: Part (e) Explanation

In ${\mathrm{BCl}}_3$, the electronegativity difference between boron and chlorine results in not even sharing of electrons between a covalent bond i.e., in a B−Cl.

Thus, ${\mathrm{BCl}}_3$ is a polar molecule.

Step 1: Part (f) Given Information

To determine whether ${\mathrm{SCl}}_2$is a polar or non-polar molecule.

Step 2: Part (f) Explanation

The polar nature of ${\mathrm{SCl}}_2$ is due to its bent shape and non-symmetrical molecule which occurs due to the presence of lone pair of electrons.

There is an electronegativity difference between sulfur and chlorine atoms. Thus, making it a polar molecule.