Why water is a a polar molecule?

Answer 1

You need to consider two ideas: which atom in the molecule attracts electrons more strongly (more electronegative), and what is the shape of the molecule. Having the Lewis dot structure for the molecule helps.

Oxygen attracts electrons more strongly than hydrogen - so the electrons tend to spend more time closer to the oxygen.

Since the shape of a water molecule is angular, not linear, the oxygen end tends to be more negative than the hydrogen end = polar molecule. (It is the presence of two unshared electron pairs on the oxygen that causes the molecule to be angular).

Answer 2

H-O-H
Actually, you have to imagine the molecule more along a V than a straight line. With the O at the junction and the H at each end.

Oxygen need the electrons from the hydrogen and vice versa. In a single atom, the electrons are evenly distributed around the atom (as they zoom around on their orbits).

However, in a water molecule, because of the asymmetry (the V shape instad of the straight line), there are always a few more electrons on one side than on the other. That side will have an overall negative charge (extremely small) while the other side will be a tiny bit positive.

Not enough charge to trigger chemical reactions. However, enough to dictate a few things like the way some molecules will dissolve (or not) or how cristalisation occurs (like the 6-sided pattern of snow flakes).

Answer 3

Atoms have a property called electronegativity. The more electronegative an atom (in a molecule) is, the greater its ability to hog the electrons. The less electronegative an atom is, the worse its ability to hog electrons. In water (H2O), the oxygen is more electronegative than the hydrogen, meaning the difference in their electronegativities is greater than zero. When this is the case, the molecule is said to be polar. This means that the molecule is separated into poles; a partially positive pole, and a partially negative pole.

Answer 4

In water molecule oxygen is more electronegative than hydrogen so the shared pair of electrons is attracted more towards oxygen atom.Thus oxygen gets partial - charge and hydrogen gets partial + charge.These two atoms act as two opposite poles(ends) in the water molecule.Hence
Water is polar compound.

Answer 5

Because of the dipole movement in the water molecule from the H-O bonding. The bonding effectively sends a stronger dipole movement in the direction of the oxygen atom, and hence the polarity.

Answer 6

Because the oxygen has eight electrons when bound with two hydrogens. The unpaired electrons cause the bend which polarizes the actual molecule.