CHEM 1415 1st EditionLecture 4Unit: Kinetic Molecular Theory Outline of Current Lecture 1. Review Example for Ideal Gas Law2. Dalton’s Law of Partial Pressures3. Kinetic Molecules Theory of Gases4. Real GasesCurrent LecturePV =nRTReview Example for Ideal Gas Law STP (Standard Temperature Pressure)T = 0 ℃ =273.15 KP = 1 atmV =nRTPV =(1 mol)(0.0821)(273.15)1 atmV =22.43 LDalton’s Law of Partial Pressures- The pressure of a mixture of gas is equal to the sum of the partial pressuresPtotal=PN2+PO2+PCO2+PAr+…Ptotal=nN2RTV+nO2RTV+nCO2RTV+nArRTV+…These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute. N231.929 78.1 %O28.567 21 %CO20.013Ar❑0.382other 0.002Ptotal=(nN2+nO2+nCO2+nAr)RTVxi=nintotalKinetic Molecules Theory of Gases1. gas – made up of particles in constant motion2. particles are very small – occupy no volume3. particles move in straight lines until colliding with each other or the walls of the entrancea. collisions are elastic ≡ kinetic energy is conserved4. particles interact only by collidinga. no repulsions or attractions5. average kinetic energy α K temperature- P α1V (with T, n constant) o larger volume →longer distance for particles to travel → fewer collisions with the wall → lower pressure- V α T (with P, n constant) o increase temperature →increase the velocity of the particles → to keep pressure constant , volume must increase- V α n (with P, T constant) o because – no volume for the particles – no interaction between the particles→ only depends on number of particlesReal Gases- Break down in PV = nRTo #2 volume of particles no longer negligible at high pressureo #3 to get sticky collisions at low temperatures, large attractions between particles(P+a n2V2)(V −nb)=nRT- a – attractions between molecules- b – related to the volume of the gas
View Full Document