Properties of gases

• Diffusion


  High concentration to low concentration
• Properties of Gases


  • Temperature in Kelvin (K)
  • Pressure in Pa
  • Volume in m³
• 0°C = 273K
• Experiment to measure pressure

  Barometer
• Boyle's Law


  At constant temp, vol of fixed mass of gas is inversely proportional to its pressure
• Charles' Law


  Fixed mass of gas at constant pressure is directly proportional to the temp
• Brownian movement


  • Constant, random, straight line of particles
• Avogadro's Law


  Same no. of particles in 1L of any gas at STP (22.4L)
• 1L of gas at RTP = 24.4L
• Ideal Gas Equation


  PV = nRT
• Real Gases


  • Differ from ideal gases due to contradictions
  • Most like ideal at high temp and pressure
• Assumptions of Kinetic Theory of Gases


  • Continuous rapid random movement
  • No attractive or repulsive forces
  • Volume is negligible
  • Collisions are perfectly elastic
• No such gas exists that obeys all assumptions of kinetic theory
• Ideal Gas


  Obeys all assumptions of kinetic theory under all temp and pressure
• General Gas Law


  PV/T = constant
• Gay-Lussac's Law of Combining Volumes


  Ratio of small whole numbers
• If you know the mass of a thing, you can find the moles of anything
• Contradictions: There may be attractive forces when particles move close together
• Inversely proportional: as one increases the other decreases.