Polar covalent molecules exhibit dipole moment. Dipole moment is equal to the product of charge separation , q and the bond length d for the bond. Unit of dipole moment is debye. One debye is equal to `10^(-18)` esu cm.
Dipole moments is a vector quantity. It has both magnitude and direction. Hence, dipole moment of a molecule depends upon the relative orientation of the bond dipoles, but not on the polarity of bonds alone. A symmetrical structure shows zero dipole moment. Thus, dipole moment helps to predict the geometry of a molecules. Dipole moment values can be distinguish between cis- and trans- isomers, ortho, meta and pare-forms of a substance, etc.
Q. A diatomic molecule has a dipole moment of 1.2D. If the bond length is `1.0times10^(-8)` cm, what fraction of charge does exist each atom?

Options

A. `0.1`
B. `0.2`
C. `0.25`
D. `0.3`

Answer

C

Explanation

Fraction of charge`=(1.2times10^(-18))/(4.8times10^(-10)times10^(-8))=0.25`