Practice portal › Electric Potential and Capacitance › Capacitance and Dielectrics

Which of the following options is the pair of polar molecules?

Asked in GUJCET 2021 · Polarisation and bound charge

Answer: (3) [HCl, H₂O]

Step-by-step solution

A polar molecule has a permanent electric dipole moment: the centres of its positive and negative charge do not coincide.

HCl: chlorine pulls the shared electrons towards itself, so the chlorine end is negative and the hydrogen end positive.

H₂O: the molecule is bent, at about 104.5°, so the two O–H dipoles do not cancel.

H₂ and O₂ are made of identical atoms, which share electrons equally, so they have no permanent dipole.

So the pair of polar molecules is [HCl, H₂O].

Why the other options are wrong

More Capacitance and Dielectrics questionsAll Capacitance and Dielectrics questions →

Reading this solution needs no sign-in. You only sign in to practise against the clock and keep your progress.

Practise this with a timer