Classifying intermolecular forces by molecular structure and polarity Steps: - Confirm all compounds have strong covalent intramolecular bonds; classify intermolecular forces based on polarity and functional groups. - Assign substance 1 to polar molecules with dipole-dipole but no H-bonding: CH3Cl (electronegative Cl creates permanent dipole). - Assign substance 3 to molecules with strong H-bonding: H2O (two O-H bonds enable extensive network). - Assign substance 2 to molecules with weaker intermolecular forces: CH3OH (H-bonding present but weaker than H2O due to single O-H and larger nonpolar CH3 group reducing overall attraction). Why C is correct: - Matches definitions: CH3Cl for substance 1 (permanent dipole-dipole from C-Cl polarity), CH3OH for substance 2 (weak forces via less effective H-bonding, boiling point 65°C vs. H2O's 100°C), H2O for substance 3 (hydrogen bonding with multiple sites per molecule). Why the others are wrong: - A: CH3Cl and CH2Cl2 both show dipole-dipole (no weak forces distinction); CH3CH2OH fits only H-bonding. - B: CH2Cl2 and CH3Cl both show dipole-dipole (duplicate for substance 1); CH3OH fits H-bonding. - D: All (CH3CH2OH, CH3OH, H2O) show H-bonding (no dipole-dipole or …