Gas Laws

Animations of Basic Gas Laws http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/gasesv6.swf (animation with audio)

Boyle’s Law V  1/P (T = constant ) Pressure  Volume = Constant P1V1 = P2V2

Boyles Law

Charles’s Law The volume of a gas is directly proportional to temperature, and extrapolates to zero at zero Kelvin.

Charles Law

b = proportionality constant T is always in Kelvin!!! Charles’s Law V  T (P = constant ) V = bT (P = constant) b = proportionality constant T is always in Kelvin!!!

Charles’s Law P = constant

Avogadro’s Law For a gas at constant temperature and pressure, the volume is directly proportional to the number of moles of gas.

a = proportionality constant V = volume of the gas Avogadro’s Law V  n (P and T = constant ) V = an a = proportionality constant V = volume of the gas n = number of moles of gas

Ideal Gas Law An equation of state for a gas. “state” is the condition of the gas at a given time. PV = nRT

Ideal Gas Law PV = nRT R = proportionality constant = 0.08206 L atm  mol P = pressure in atm V = volume in liters n = moles T = temperature in Kelvins

PV = nRT Variables on the same side of the equation are inversely proportional Variables on opposite sides of the equation are directly proportional

Standard Temperature and Pressure “STP” P = 1 atmosphere T = C = 273K The molar volume of an ideal gas is 22.42 liters at STP

A balloon inflated in an air- conditioned room at 27oC, has a volume of 4 L. It is heated to a temperature of 57oC. What is the new volume of the balloon if the pressure remains constant

The gas left in an used aerosol can is at a pressure of 1 atm at 27oC The gas left in an used aerosol can is at a pressure of 1 atm at 27oC. If this can is thrown unto a fire, what is the internal pressure of the gas when its temperature reaches 927oC

A container with an initial volume of 1 L is occupied by a gas at a pressure of 1.5 atm at 25oC. By changing the volume, the pressure of the gas increases to 6 atm as the temperature is raised to 100oC. What is the new volume?

A gas occupies a volume of 180 mL at 35. 0oC and 740 mm Hg A gas occupies a volume of 180 mL at 35.0oC and 740 mm Hg. What is the volume of the gas at conditions of STP?