Identify the strongest attractive force present in the pure substances shown: London forces, dipole-dipole, hydrogen bonding, ion-dipole, or ionic attractions.

Question

CH₃CH₂CH₂CH₂OH, KCl, CH₂Cl_2, CH₃OCH₂CH₃

Answer 1

CH₃CH₂CH₂CH₂OH: Hydrogen bonding because of the presence of the OH group.

KCl: Ionic attractions because the hydrated K+ and Cl- ions exhibit coulombic forces of attraction.

CH₂Cl₂: Intermolecular forces will depend on the isomer present. If it is a cis isomer, then the strongest attraction will be dipole-dipole, but if it is a trans isomer, then there will be no dipole, and it will be London forces.

CH₃OCH₂CH₃: There is no hydrogen bonding but this molecule is polar (bent shape around the O atom), so there will be dipole- dipole interactions.