SCIENCE PRE-FINALS

• Gas Law Properties


  • Volume (V)
  • Pressure (P)
  • Temperature (T)
  • Amount of Gas (n)
• Volume (V)


  The total space occupied by a gas. The size of a sample of gas is the same size of its container.
• Pressure (P)


  The force exerted by the gas on its container.
• Temperature (T)


  The total heat (Kinetic Energy) of its particles.
• Amount of Gas (n)


  The total number of particles of gas present, expressed in moles (mol).
• Units of Gas Law Properties

  • L
  • mL
  • m3
  • cm3
  • Atm
  • Torr
  • Psi
  • Pa
  • °F
  • °C
  • K
  • mol
• Boyle's Law


  • The volume of a fixed amount of gas is inversely proportional to its pressure.
  • When one property increases, the other decreases
• Charles' Law


  • At constant pressure, the volume of a fixed amount of gas is directly proportional to the Kelvin (K) temperature.
  • When one property increases, the other property also increases
• Gay-Lussac's Law


  • The pressure of a gas is directly proportional to its Kelvin temperature if the volume and amount of gas is constant.
• Combined Gas Laws


  Combining the relationship among pressure, volume, and temperature to derive the combined gas law equation
• Avogadro's Law


  • At constant temperature and pressure, the volume of a gas is directly proportional to the number of moles of the gas present.
• Ideal Gas Law


  • The volume and pressure of a gas varies directly with the number of its molecules and the absolute temperature.
• R


  0.0821 atm•L/mol•K
• Gas Law Properties, Observed, Relationship, Equation


  • Boyle's Law: P and V, T and n, V α 1/P, P1V1 = P2V2
  • Charles' Law: V and T, P and n, V α T, V1/T1 = V2/T2
  • Gay-Lussac's Law: P and T, T and n, P α T, P1/T1 = P2/T2
  • Combined Gas Laws: P, V, and T, n, P V α T, P1V1/T1 = P2V2/T2
  • Avogadro's Law: V and n, P and n, V α n, V1/n1 = V2/n2
  • Ideal Gas Law: P, V, T, and n, R, P V α n T, PV = nRT
• Converting units of temperature

  1. °F to °C: (°F - 32) * 5/9

  2. °C to K: °C + 273.15
• Kinetic Molecular Theory


  • Gases consist of very tiny molecules.
  • The distance between gas molecules are large and the volume of a gas is mostly empty space.
  • There is no forces of attraction between and among gas molecules. Unlike solids and liquids, gas particles do not attract each other and would try to move far away from each other as far away as possible (diffusion).
  • Gas molecules are in constant, random, and straight-line motion. They collide frequently with one another and with the walls of the container. No energy is lost during collision.
  • The average kinetic energy for molecules is the same for all gases at the same temperature.