Avogadro’s Law We Know That 1 Mole of Gas = __________ L Avogadro looked at the relationship between volume and the number of moles of gas He found: For a gas at constant temperature and pressure, the volume is directly proportional to number of moles of gas. V1 / n1 = V 2 / n2 Example: Sample 1 of oxygen gas is 10 L and 0.50 mol. Sample 2 of oxygen gas occupies 40 L, how many moles of oxygen are in Sample 2? Ideal Gas Law If we combine Boyle’s, Charles’, and Avogadro’s Laws, we can then see how pressure, volume, temperature, and moles all interrelate. PV = nRT P = Pressure (atm) V = Volume (L) n = number of moles (mol) R = Universal Gas Constant = .08206 (atm*L/mol*K) T = Temperature (K) Example: A sample of neon has a volume of 9.4 L at a temperature of 0˚C and a pressure of 2 atm. Calculate the number of moles of neon in this sample.