When very electronegative atoms , like oxygen , bond to atoms with lower electronegativity , like hydrogen , what's the result?

Electronegative atoms or atoms where electrons spend more of their time orbiting the atom's nucleus giving the atom a negative charge. When electronegative atoms such as oxygen bond to hydrogen they pull the hydrogen's electron to themselves becoming even more electronegative. This causes the hydrogen side to become positive. The molecule formed is a polar molecule. Molecules with positive ends and negative ends are called polar.