characteristics of gas -
- possible for substance to coexist as solid, liquid, and gas at the same time
- vapor - gaseous form of a substance normally existing as liquid/solid
- expands to fill the container it’s in (gas volume = volume of container)
- pressure added to gas >> gas gets compressed easily >> volume decreases
- form homogeneous mixtures (regardless of type of gases involved)
pressure - force acted upon a given area
- P = F/A
- newton (N) - SI unit for force, kg-m/s2
- pascal (Pa) - SI unit for pressure, N/m2
- kPA = 1000 Pa
- bar = 105 Pa, approximate atmospheric pressure at sea level
- barometer - invented by Evangelista Torricelli, measures atmospheric pressure
- manometer - used to measure pressure of liquids/gases, similar to barometer
- standard atmospheric pressure = pressure needed to support column of mercury 760 mm high
- atm = 760 mm Hg, 760 torr = 1.01325 x 105 Pa = 101.325 kPa
- 1 torr = 1 mm Hg
Boyle’s Law - pressure-volume relationship
- volume of gas (at constant temperature) inversely proportional to pressure
- P1V1 = P2V2
Charle’s Law - temperature-volume relationship
- volume of gas (at constant pressure) directly proportional to temperature
- V1/T1 = V2/T2
Avogadro’s Law - quantity-volume relationship
- law of combining volumes - at given pressure/temperature, volumes of reacting gases exist in simple ratios
- equal volumes of gases at same temperature/pressure have equal numbers of molecules
- volume of gas (at constant pressure/temperature) directly proportional to number of moles of gas
- V = constant x n
Subject:
Subject X2:
