COMMON PROPERTIES OF GASES

• Gases


  • Easy to compress
  • Expand to fill their containers
  • Occupy far more space than the liquids or solids from which they form
• Gases


  • Molecules move independently from each other
  • Most are colorless
  • Flammable like hydrogen
• Gas particles


  1. Spread about or diffuse

  2. Fill all the space in any container
• Gases


  • Very low density
  • Very low viscosity
• It is possible to measure the density, mass, volume, temperature and pressure of gases
• Commonly used units for volume

  • Cubic meter
  • Cubic decimeter
  • Cubic centimeter
  • Liter
  • Milliliter
  • Quart
  • Gallon
• 1 milliliter = 1 cubic centimeter
• Commonly used units for pressure

  • Pascal
  • Atmosphere
  • Millimeters of mercury
  • Centimeters of mercury
  • Torr
  • Pound per square inch
• 1 atmosphere = 760 millimeters of mercury = 76 centimeters of mercury = 760 Torr = 101,325 Pascal = 14.6956 pounds per square inch
• Temperature units:

  Celsius

  Fahrenheit

  Kelvin
• 0 degrees Celsius = 273.15 Kelvin

  0 degrees Celsius = 32 degrees Fahrenheit
• Temperature unit conversions


  • 38 degrees Celsius = 311.15 Kelvin

  40 degrees Fahrenheit = 4 degrees Celsius
• At standard temperature and pressure (STP), 1 mole of gas occupies 22.4 liters
• Kinetic molecular theory of gases

  • Volume occupied by gas particles is negligible

  Gas particles exert no attractive forces

  Gas particles in constant random motion

  Collisions are completely elastic

  Average kinetic energy proportional to absolute temperature
• Kinetic molecular theory explains gas laws like Boyle's law and Charles' law
• gases can flow like liquids
• 1 liter = 1 cubic decimeter
• 1 cubic meter = 1000 liters
• SI units (volume) are cubic meter, cubic decimeter, and cubic centimeter
• metric units (volume) are liter and milliliter
• english units (volume) are quart and gallon
• SI unit (pressure) is Pascal (Pa)
• metric units (pressure) are atmosphere (atm), milliliters of mercury (mm Hg), and centimeters of mercury (cm Hg)
• english units (pressure) are torr and lb/in^2 (psi)