Identify the correct statements from the following.
(1) The dipole moment of `CO_(2) and BF_(3)` is zero
(2) The dipole moment of `NF_(3)` is higher than the diople moment of `NH_(3)`
(3) The dipole moment of HI is lower than the dipole moment of HCl

Options

A. 1, 3
B. 1, 2
C. 2, 3
D. 1, 2,3

Answer

A

Explanation

1. The `BF_(3)` molecule has a symmetrical trigonal planar geometry, the moment of any two B-F dipoles is equal in magnitude but opposite in direction to the moment of the `BF_(3)` molecule is zero. Same as `CO_(2)`.
2. In `NH_(3)`, N is more electronegative than H so, N pulls the electrons from H towards itself so, the direction of moment due to the N-H bonds is in the same direction as that of the long pair of electrons on nitrogen.

But in case of `NF_(3), H **` [lone pair] moment is in the opposite direction to the N-F bond moments.
Thus, has smaller net dipole moment.
3 `:.` Size of I-atom is more than of Cl-atom and electronegativit of I-atom is less than of Cl-atom. Hence, HI has lower dipole -moment than HCl.