 The kinetic theory assumes the following concepts about gasses are true:  Gas particles do not attract or repel each other  Gas particles are much smaller than the distances between them.  Gas particles are in constant, random motion.  No kinetic energy is lost when gas particles collide with each other or with the walls of their container (elastic collisions).  All gasses have the same average kinetic energy at a given temperature.

 The following four variables work together to determine the behavior of gasses:  Temperature  Pressure  Volume  Number of particles present

 STP = Standard Temperature and Pressure =0.00 ⁰C and 1.00 atm.  Temperature: Kelvin (K) ONLY!!!!  ⁰C = K

 Pressure: Atmospheres (atm) ONLY!!!  1 atm = kPa  1 atm = 760 mm Hg  1 atm = 760 torr  1 atm = 14.7 psi  Volume: Liters (L) ONLY!!!!!  1000 mL = 1 L

 When pressure increases, volume will decrease (with constant temperature)  When pressure decreases, volume will increase (with constant temperature)  P 1 V 1 = P 2 V 2  P = Pressure  V = Volume

ITS ALL ABOUT PRESSURE AND VOLUME P 1 V 1 = P 2 V 2

 As temperature increases, so does the volume of a gas sample when the pressure is held constant.  This is because at higher temperatures, gas particles move faster and strike each other and the walls of the container more frequently and with greater force.  For the pressure to stay constant, the volume must increase so the particles have further to travel before striking the walls.

 Avogadro’s Principle states that equal volumes of gasses at the same temperature and pressure contain equal number of particles.  Remember from ch 11: 1 mole contains × particles  The molar volume for a gas is the volume that one mole occupies at 0.00 ⁰C and 1atm pressure. AKA STP.  Avogadro showed that one mole of any gas will occupy a volume of 22.4L at STP.  Because the volume of one mole of a gas at STP is 22.4L, you can use the following conversion factor to find moles, mass or particles in a gas sample  22.4L = 1 Mole