Intermolecular Forces

What explains the very high melting and boiling point of water

• Strong dipole-dipole bonds between water molecules
• Strong hydrogen bonds between water molecules
• Dispersion forces which are present in all molecules
• Asymmetrical shape of the polar bonds.

Hydrogen bonding occurs when hydrogen is bonded to N, O, or F.  Which of the following has hydrogen bonding?

• CBr₄
• NO₂
• H₂S
• NH₃

Does H₂O have hydrogen bonding?

• yes
• no

Does HF have hydrogen bonding?

• yes
• no

Does HCl have hydrogen bonding?

• yes
• no

Does CH₄ have hydrogen bonding?

• yes
• no

Does NH₃ have hydrogen bonding?

• yes
• no

Which is the second strongest intermolecular force, after hydrogen bonding?

• dipole-dipole attraction
• London forces

All molecules have London forces between them, but dipole-dipole and hydrogen bonding are so much stronger that when they are present we can ignore London forces.  Which of these has ONLY London forces?

• I₂
• NH₃
• OCl₂
• SH₂

Which substance would have the weakest intermolecular forces of attraction?

• CH₄

• NaCl

• H₂O

• MgF₂