What do I mean by "polar?" I mean that the electric charge in a molecule of water is distributed unevenly. Water, as we all know, is two atoms of hydrogen bound to a single atom of oxygen. In exactly the same fashion as we discussed earlier, oxygen gets an unfair share of the electron clouds from the two hydrogens. The result is a little molecule that bears a slight d - on one end and a slight d + on the other, as shown in Figure 10. Compare this situation to ethane, an organic molecule also pictured in Figure 10. Ethane is two carbon atoms bonded to each other, with each carbon carrying three hydrogens. The carbon atoms are not especially electrophilic, and the molecule is symmetrical anyway, so the electron density is evenly distributed over the molecule. Ethane, unlike water, is nonpolar.