Question

Molecules possessing dipole moment are:

• A. ${CH}_4$
• B. $H_{2}O$
• C. $H_{2}S$
• D. $Si{Cl}_4$

Answer 1

Answer: (B), (C)

$H_{2}S$
$H_{2}O$

$H_{2}O$ and $H_{2}S$ shows dipole moment.
Dipole moment of $H_{2}O$ is $1.85D$.There is a bond dipole moment pointing from each $H$ to the $O$, making the oxygen partially negative and the hydrogen partially positive. In addition, the $O$ also has nonbonded electrons in the direction opposite the hydrogen atoms.Hence $H_{2}O$ is polar molecule.
Dipole moment of $H_{2}S$ is $0.97D$. $H_{2}S$ is a bent molecule.Hence $H_{2}S$ shows dipole- dipole interacton and is polar molecule.