Chapter 21.4, Problem 22R

To determine

Polar and nonpolar molecules.

Answer to Problem 22R

When there is electronegativity difference between the bonded atoms then polar molecules occur.

When electrons are shared between atoms in the molecules then nonpolar molecules occur.

Explanation of Solution

Polar molecules:

Polar molecule has a dipole, partially positive and partially negative. Polar molecules have asymmetric shape, lone electron pair, or central atoms with different electronegativity values. For example: water, ammonia,ozone

Nonpolar molecules:

Non polar molecules are symmetrical so that dipole charges cancel each other and net dipole moment is zero. For example: carbon dioxide, benzene.

Conclusion:

Polar molecules occur when two atoms do not share electron equally in a covalent bond.

Nonpolar molecules occur when two atoms share electron in a covalent bond.