forces of attraction

• what are intermolecular forces?


  forces of attraction or repulsion which act between neighbouring particles; atoms, molecules, or ions
• what are hydrogen bonds?

  A strong dipole-dipole attraction between molecules that contain a hydrogen atom bonded to a small, highly electronegative atom
• what are dipole-dipole forces?

  The attractions between oppositely charged regions of polar molecules
• liquid?


  A form that flows, has a constant volume, take the shape of its container, in constant motion, can form hydrogen bonds and have a high surface tension
• solid?


  A form of matter that has its own definite shape and volume, is incompressible and expands only slightly, more dense than liquids, particles are closely packed together and are limited to vibrations around fixed location
• viscosity?


  A measure of the resistance of a liquid to flow, which is affected by the size and shape of particles, and generally increases as the temperature decreases and as intermolecular forces increase
• boiling point?


  The temperature at which a liquids vapor pressure is equal to the external or atmospheric pressure
• freezing point?


  temperature at which a liquid is converted into a crystalline solid
• melting point?


  Temperature at which the forces holding a crystalline lattice together are broken
• condensation?


  Gas—liquidEnergy is released
• deposition?


  Gas—solidEnergy is released
• freezing?


  Liquid—solidEnergy is released
• vapourisaton?


  Liquid—gasEnergy is required
• sublimation?


  Solid—gasEnergy is required
• melting?


  Solid—liquidEnergy is required