How to solve this and solution?

Question

A hypothetical molecule, X–Y, has a dipole moment of 1.35 D and a bond length of 175 pm.

Calculate the percent ionic character of this molecule.



percent ionic character:

Answer 1

% ionic character = observed dipole / theoretical dipole) x 100%

First we will find the theoretical dipole (charge on electron in coulombs x bond length in meters):

(1.6x10^-19 C) ( 175x10^-12 m) = 2.8x10^-29 Cm

2.8x10^-29 Cm x 1 D / 3.336x10^-30 Cm = 8.39 D = theoretical dipole (in Debye units)

Percent ionic character = observed dipole / theoretical dipole:

% ionic character = 1.35 D / 8.39 D (x100%) = 16.1% ionic

(be sure to check the math)