Distinguish between a polar bond and a polar molecule To which does the term dipole refer?
(b) Which is having the higher b.pt: `Br_(2)` or `ICI`
(c ) Can a molecule have a dipole moment if it has no polar covalent bonds
(ii) How is it possible for a molecule to have polar bonds but no dipole moment?
(d) Arrange in decreasing polarity of bonds `SbH_(3),AsH_(3),PH_(3),NH_(3)` , .

Explanation

A polar bond is formed between two atoms of different `EN` A polar molecule results when there is only one polar bond or when more than one polar bond within it is not sufficiently oriented to cancel the effects of the others The polar molecule is often referred to as having a dipole moment
(b) Both of these molecules have same number of electrons but `ICI` has a dipole moment `So,ICI` have higher b.pt
(c) No (ii) If the various polar bonds are arranged symmetrically as in `CO_(2)` and `C CI_(4)` the effects of one bond are canclled by the effects of the other (s)
(d) Greater the difference in `EN` of the atoms, more polarity of bonds
.