The electronegativity of Oxygen is higher than that of H, thus the electrons tend to stay a little more on the oxygens electron orbitals, right?
[/URL]CO2 is a linear molecule; the two polar bonds point in opposite directions, and cancel each other out.
Since H20 is a bent molecule, the two polar bonds don't cancel each other.
Here's an image of a water molecule: the left side is more negative than the right side, resulting in an overall dipole moment for the molecule:
Do you own a General Chemistry text? I would suggest purchasing one, these are things that are pretty clearly explained in the text that I own.
As far as your current question: