What is a Gas?	One of the states of matter [solid, liquid, gas, plasma...] Very energetic Made of atoms, therefore has mass Could be element or compound with specific chemical formula Low density = mass/volume Unit: g/mL or g/cubic centimeter , molecules far apart No definite shape, volume May have color or odor or taste May be difficult to see Hard to hold on to Can be compressed [and change to liquid or solid] Expand when heated; fills container Can be poisonous, deadly, flammable, explosive, corrosive, polluting, helpful, necessary for life.... Some don't react [Noble gases have all possible valence electrons so they don't have to react] May change voice or make you fall asleep if inhaled [anesthetic gases] Either naturally occurring [BrINClHOF gases, those diatomic "twins"] or made in chemical reactions Used in many things [cars & stoves as fuel, to make other things...] Found in atmosphere of every planet Necessary for life Excited gases make light
	What laws do gases follow? Calculate it!	Boyle's law PV=kT P1V1=P2V2 pressure is inversely related to volume Charles' law V=kT V1T2 = V2T1 V1/T1 = k = V2/T2 volume is directly proportional to temperature Avogadro's law V = k n [n=# moles] equal volumes of gases at same temp & pressure contain equal number of particles Dalton's law sum of partial pressures of all components of a gas mixture equals the total pressure of the gas Ideal gas law PV=nRT n= moles R=0.0821 L atm/mol K R=8.314 Joules/mol K
	What are some of the problems with gases in our atmosphere?	Ozone hole Greenhouse effect Global warming Acid rain
	latest update: 14 July, 2002	SD Loder

this page: http://howard.nebrwesleyan.edu/hhmi/fellows/sloder/gas.html

  back | to chemistry home | Loderland | front door