finals

• Solids


  • Molecules simply vibrate and rotate in place rather than move about
  • Held together by ionic or strong covalent bonding
  • Attractive forces between the atoms, ions, or molecules are very strong
  • Particles are held in fixed positions and have very little freedom of movement
  • Have definite shapes and definite volumes and are not compressible to any extent
• Crystalline solids


  • Atoms, ions, or molecules that make up the solid exist in a regular, well-defined arrangement
  • The smallest repeating pattern is known as the unit cell
• Amorphous solids


  • Do not have much order in their structures
  • Molecules are close together and have little freedom to move, but are not arranged in a regular order as in crystalline solids
• Types of Solids


  • Ionic solids
  • Metallic Solids
  • Molecular Solids
  • Network Solids
  • Amorphous Solids
• Ionic solids


  Held together by electrostatic interactions between cations and anions
• Metallic Solids


  Held together by attraction among positively charged metal atom cores and valence electrons
• Molecular Solids


  Held together by intermolecular interactions such as London forces, dipole-dipole, and hydrogen bonding
• Network Solids


  Bonded together into infinite molecules by covalent bonds between atoms
• Amorphous Solids


  Held together by covalent bonds but no long-range repeating pattern
• Solution


  • A homogeneous mixture
  • Uniform distribution of solution
  • Two solutions made up of same substances may have different composition
  • May be gas, liquid, or solid
  • Particle size distinguishes solutions from other mixtures
• Solute


  Generally the substance present in relatively small amount
• Solvent


  The medium where solutes are dissolved
• Concentrated


  Relatively large quantity of solute dissolved
• Dilute


  Relatively small quantity of solute dissolved
• Types of Solutions


  • Saturated
  • Unsaturated
  • Supersaturated
• Saturated solutions


  Have concentrations at the solubility limit for a given temperature
• Unsaturated solutions


  Have concentration less than the solubility limit
• Supersaturated solutions


  Concentration of solute is greater than the normal solubility limit, facilitated by an increase in temperature
• Miscible solutions


  Two liquids dissolve in each other in all proportions
• Immiscible solutions


  Two liquids that are insoluble to each other are paired
• Factors Affecting Solubility


  • Intermolecular Forces
  • Partial Pressure of Solute Gas over Liquid Solution
  • Temperature
• Substances that are held together by the same type of intermolecular forces exhibit increased levels of solubility
• Increased partial pressure of a solute gas over a liquid increases its solubility and vice versa
• Solubility of solid-liquid and liquid-liquid solutions increases with rising temperature
• Solubility of gas-liquid solutions decreases with rising temperature
• Energy


  The capacity to do work
• Types of Energy


  • Kinetic Energy
  • Potential Energy
• Kinetic Energy


  Energy in motion
• Potential Energy


  Energy resulting from position
• Energy Units


  • Joules (J)
  • Calories (cal)
• The law of conservation of energy states that energy can neither be created nor destroyed- the total energy of the universe is constant
• Heating


  An energy transfer process that happens when two samples of matter at different temperatures are brought into contact
• Internal Energy


  The sum of the individual energies of all nanoscale particles
• ΔE = Efinal - Einitial
• If ΔE > 0 internal energy increases, if ΔE < 0 internal energy decreases
• ΔE = q + w

  q = quantity of energy by heating, w = quantity of energy by doing work, ΔE = change in internal energy
• Heat Capacity


  The quantity of energy required to increase the temperature of that sample by one degree
• Specific Heat Capacity


  Quantity of energy needed to increase the temperature of one gram of a substance by one degree Celsius
• Molar Heat Capacity


  Quantity of energy that must be transferred to increase the temperature of one mole of a substance by one degree Celsius