Question

9 Carbon tetrachloride $\left({\text{CCl}}_4\right)$ is a liquid whose molecules are symmetrical and so are not permanent dipoles, unlike water molecules. Explain briefly how the effect of an external charge on a beaker of water $\left({\text{H}}_{\text{2}}\text{O}\right)$ differs from its effect on a beaker of ${\mathbf{\text{CCl}}}_{\mathbf{4}}$. (Hint: Consider the behavior of the permanent dipole you made out of U and L tapes.)

Short answer

Carbon tetrachloride molecules are symmetric dipoles with no torque, and they are not orientated owing to an electric field formed by an electric charge, since they do not conduct electricity.

Step-by-step solution

Concept/Significance of electric dipole moment

The distance between positive and negative electrical charges is measured by the electric dipole moment. So, a dipole's dipole moment determines the intensity and direction of the field everywhere.

Explanation of the effect of an external charge on a beaker of water (H2O) differs from its effect on a beaker of CCl4

In carbon tetrachloride the electron charge density is closer to chlorine, which is more electronegative than carbon, the CCl4 molecule is polar, and the C-Cl bonds have a zero-dipole moment. Carbon tetrachloride is a white liquid with a pleasant odour akin to ether and chloroform. It has the chemical formula CCl4 and is a covalent and volatile molecule with a denser vapour than air. It is not combustible or conductive of electricity. Unlike water molecules, which act as asymmetric dipoles and are orientated according to an electric field formed by a nearby electric charge, carbon tetrachloride molecules are symmetric dipoles without torque and are not directed owing to an electric field created by an electric charge, as they do not have electron movement.

Thus, carbon tetrachloride molecules are symmetric dipoles with no torque, and they are not orientated owing to an electric field formed by an electric charge, since they do not conduct electricity, that is, they do not have electron movement.