behaviour of gasses

• Ludwig Boltzmann and James Clerk Maxwell

  • explained the physical properties of gas in the 19th century
• Assumptions of the Kinetic Molecular theory of Gasses 

  1.The molecules of gasses are far apart from one another, separated in distances larger than their own size. Gas molecules possess gas, but their volume is negligible.

  2. The molecules of gas are always in constant random motion, frequently colliding with one another. The collisions are perfectly elastic

  3. The particles of an ideal gas exert no attractive forces on one another or their surroundings.

  4. The average kinetic energy of a gas molecule depends on the absolute temperature of the gas.
• the Physical Qualities of Gases are

  Pressure, Volume, Temperature, Amount of Substance
• Pressure

  force divided by the total surface area

  • Units of measurement: standard atmospheric pressure (atm), millimeter of mercury (mmHg), torr, and kilopascal (Pa) 
• Volume

  generally defined as space occupied by matter, this is the space where gas molecules are moving

  • Units of measurement: liter (L), milliliter (mL), cubic centimeter (cm^3), and cubic meter (cm^3)
• Temperature

  measure of how hot or cold a substance is

  • gas molecules move faster in higher temperatures and slower at lower temperatures
• • thermometer- used to measure the temperature of gasses
• Amount of Substance

  • The amount of substance
  • Units of measurement: moles (mol)
• Boyle’s Law- volume is INVERSELY proportional to pressure 
• Charles's Law- volume is DIRECTLY proportional to temperature
• Gay-Lussac’s Law- pressure is DIRECTLY proportional to temperature
• Avogadro’s Law- volume is DIRECTLY proportional to the amount/number of moles
• French scientists Jacques Charles and Gay-Lussac investigated that, at constant pressure the volume of gas contracts when cooled and expands when heated
• Charles’s law states that the volume of a fixed amount of gas is directly proportional to the absolute temperature of gas at constant pressure 
• Gay-Lussac 's Law- as pressure increases, so does the temperature