CHEM 151 1st Edition Lecture 6 Outline of Last Lecture I. Phase Changes and Phase DiagramsII. ApplicationOutline of Current Lecture III. A Particulate Model of MatterIV. Temperature and Kinetic EnergyV. Mass and Kinetic EnergyVI. Interparticle ForcesVII. Explaining Phase TransitionsCurrent LectureBasic assumptions:1. Any macroscopic sample is composed of a large number of particles.(1 mL of water = 3.34 x 1022 molecules) 2. Particles are constantly moving. (Translation, rotation, vibration, etc.)3. Particles interact with each other. The nature and strength of the interactions depends on distance. In microscopic terms, Pressure = Force / Area.Absolute temperature is measured in Kelvin. T(K) = T(˚C) + 273.15Measure of average kinetic energy per particle. KE= 1/2 mv2If you increase the temperature, you are also increasing the speed.If particles have a larger mass, at the same temperature, they are moving slower on average. Interparticle Forces:1. Solids (strongest)2. Liquids3. Gases (weakest)Interactions between particles determine much of the differences between substances. When the differences are very small (attractive forces are very weak), the substances behave very similarly.During a phase transition, all of the energy is invested or lost in the form of potential energy. Energy is needed to break bonds.Energy is released when bonds are formed.The total kinetic energy does not change during