Question

Which of the following molecules does not possess a permanent dipole moment?

• A. $C{S}_2$
• B. $S{O}_3^{2-}$
• C. $H_{2}S$
• D. $S{O}_2$

Answer 1

The correct option is A $C{S}_2$

Dipole moment is a vector quantity.

$S{O}_3$

$S{O}_3$ has a trigonal planar structure.

In it, the individual S-O bond moments cancel out each other so that the net dipole moment is zero.

i.e., µ = 0 for $S{O}_3$

$S{O}_2$ It has a bent structure due to the presence of one lone pair.

Is a polar molecule.

In it, the individual S-O bond moments do not cancel out each other so that the net dipole

moment is not zero.

It has a permanent dipole moment.

$H_{2}S$

It has a bent structure due to the presence of one lone pair.

Is a polar molecule.

In it, the individual H-S bond moments do not cancel out each other so that the net dipole

moment is not zero.

It has a permanent dipole moment

$C{S}_2$

$C{S}_2$ is one of the molecules which does not possess a dipole moment.

It is a linear molecule and therefore it does not have a permanent dipole moment.