Which one of the following molecules does not have a dipole moment?

Which one of the following molecules possesses a molecular dipole?

• Which one of the following molecules possesses a molecular dipole? O2 SO2 BeCl2 CO2 My understanding of a dipole is basically a polar molecule. Is this correct? Please explain how you got this answer?

• Answer:

  yeah basically, just look for electronegativity. The most electronegative is F, Fluorine. O2 does not have a dipole moment, since they cancel each other out SO2 has a dipole moment. Since there is resonance, the double bond on one oxygen keeps on going back and forth. CO2 does not have a dipole moment, since there are no lone pairs of electrons, the dipole on the oxygen's cancel out. BeCl2, does not have a dipole moment