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What is polar/nonpolar?

The difference between polar and nonpolar bonds as follows

Polar bonds

- Ionic bond formation takes place between atoms of strongly electropositive and strongly electronegative elements
- An element preceding an inert gas in the periodic table is strongly electronegative and the element immediately following the inert gas is strongly electropositive
- Electrovalent linkage is common in inorganic compounds like NaCl, Na2O, CaO etc.

Nonpolar bonds

Covalent bond formation, first suggested by Lewis consists in sharing or holding a pair of electrons in partnership between two combining atoms, so that the pair counts towards the electronic grouping of both atoms. By this mechanism also, the stability akin to the inert gas is attained by each atom

This type of linkage which is the result of equal contribution and equal sharing of electrons is known as covalent bond. The compound formed by electron sharing of electrons is known as covalent or nonpolar by Langmuir, 1919. The covalent compounds always exist in molecular form, are nonelectrolyte or nonionizable, soluble in organic solvents e.g. benzene, ether, pyridine etc.
 
Difference between Polar and Nonpolar Molecules

The Difference between polar and nonpolar molecules as follows

Polar molecules

A molecule in which there is a little division of charge in the chemical bonds, so that one part of the molecule has a small positive charge and the other has negative charge i.e. dipole

H2O is a good example of a polar molecule.

It forms when an atom of high electro negativity -ve e.g chlorine with hydrogen.

It aligns them because the -ve end of every molecule is attracted to the +ve end of extra molecules and vice versa.

It contains hydrogen (strongly polar) that form a bond known as hydrogen bond

Nonpolar molecules

Non polar does not have separation of charge, so it doesn’t contain positive or negative poles.

Well known example for non polar molecules is Carbon dioxide CO2

Here the electrons are dividing equally between the nuclei. So the sharing of charge is same and the force of attraction is small.

It shows small reactivity.

I highly recommend you review this video:

Ionic, Covalent, and Metallic Bonds (http://www.youtube.com/watch?v=CGA8sRwqIFg&feature=player_embedded#ws)

And this activity:

http://www.mhhe.com/physsci/chemistry/chang7/esp/folder_structure/bo/m4/s1/index.htm (http://www.mhhe.com/physsci/chemistry/chang7/esp/folder_structure/bo/m4/s1/index.htm)

If you need further clarification, reply back!