Electronegativity and bond polarity

• In a covalent bond the electron pair is not usually shared evenly between the 2 atoms unless they are the same
• • one atom will take up a slightly negative charge, the other becomes slightly positive - makes the bond polar
• • Coordinate bonds are always polar
• Pauling electronegativity values

  • most bonds joining atoms that aren’t identical will be polar to some extent
• • most ionic bonds have some covalent character