KINETIC MOLECULAR MODEL

• Solids:

  • Amorphous solids have no definite shape
  • Crystalline solids have a definite shape
  • Ionic solids have a highly ordered packing arrangement
  • Molecular solids have a less ordered packing arrangement
  • Metallic solids have a "sea of electrons" that allows for electrical conductivity
  • Network solids have a network of covalent bonds
  • Group 8A solids are noble gases
• Particles in solids are held together by intermolecular forces
• Liquids:

  • Have a definite volume but no definite shape
  • Are denser than gases
  • Are held together by strong intermolecular attractive forces but not strong enough to keep them in a rigid position
  • Are free to slide over one another
• Kinetic Molecular Model explains the properties of solids and liquids in terms of intermolecular forces of attraction and the kinetic energy of the individual particles
• Solids:

  • Have a definite volume and shape
  • Are denser than liquids
  • Are not easily compressed because particles are tightly packed
  • Interparticle attractive forces are stronger than those in liquids, keeping them rigid
  • Assume a crystalline structure when highly ordered, otherwise exist as amorphous solids
• Solids vs. Gases:

  • Gases have low density and high compressibility, filling their container
  • Solids have greater densities, are slightly compressible, and maintain their shape
• Components of a solid are close together and exert large attractive forces on each other
• Kinetic Molecular Model explains properties of solids and liquids based on intermolecular forces of attraction and kinetic energy of particles
• Intermolecular Forces of Attraction:

  • Dipole-dipole
  • Ion-dipole
  • London dispersion
  • Hydrogen bonding
• Dipole forces arise due to unequal electron distribution within molecules
• Dipole-dipole forces occur between polar molecules with permanent dipoles
• Hydrogen bonding is a strong dipole-dipole interaction between hydrogen and electronegative atoms
• London dispersion forces are the weakest intermolecular forces, present in all types of atoms and molecules
• London dispersion forces arise from continuous movement of electrons, stronger with more electrons
• London dispersion forces are the only attractive force in nonpolar molecules
• London dispersion forces create temporary dipoles in nonpolar molecules
• London dispersion forces are stronger in molecules with more electrons, like helium
• London dispersion forces are present in all atoms and molecules, whether ionic or covalent, polar or nonpolar
• London dispersion forces are the "consolation prize" of intermolecular forces
• London dispersion forces are the only intermolecular force in nonpolar molecules
• London dispersion forces are due to the movement of electrons in particles
• London dispersion forces are stronger in molecules with more electrons
• London dispersion forces are present in all atoms and molecules
• London dispersion forces are the weakest intermolecular forces
• London dispersion forces arise from continuous movement of electrons
• London dispersion forces are stronger with more electrons
• London dispersion forces are present in all types of atoms and molecules
• Density is the mass of a substance per unit volume
• Density indicates how tightly packed matter is and the amount of mass in a given space
• The Kinetic Molecular Model explains the properties of solids and liquids based on intermolecular forces of attraction and the kinetic energy of individual particles, which is dependent on the substance's temperature
• Intramolecular bonding occurs within molecules, where atoms can form stable units by sharing electrons
• Condensed states of matter include liquids and solids
• Forces that cause the aggregation of components to form a liquid or solid may involve covalent or ionic bonding, or weaker interactions known as intermolecular forces
• Intermolecular forces of attraction are the attractive forces between neighboring molecules
• Intramolecular bonds can be ionic, covalent, or metallic
• Formula units are particles of ionic compounds
• The force of attraction between neighboring molecules is weaker than that between formula units because molecular attraction involves only partial charges
• Elements with similar behavior are grouped together in the Periodic Table
• Elements in the same group have the same number of valence electrons
• Valence electrons are the electrons in the outermost shell of an atom