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Physics2 Final Exam Chapter 4 Chapter 5 Ideal gas Kinetic theory of gases Molar specific heats of an ideal gas State converting of an ideal gas Heat and first law of thermodynamics Change in entropy S.
PV = nRT = NkT nR = Nk With N = n.Na(Avodgadro) Ideal gas Where : k = 1.38 x 10^-23 NA = 6.02 x 10^23 R = 0.082 when P (atm) ; V(dm^3 = liter) R = 8.314 (Usually used) when P(Pa) ; V (m^3) T : C + 273.15 (K) The mean free path for a gas molecule Distance between two molecules or atoms With d : diameter (m) Root- mean – square speed Average speed Kinetic theory of gases Most probable speed The mean free time Average translational kinetic energy Monatomic gas > f = Diatomic gas > f = Polyatomic gas > f = Isochoric ( V constant) Isobaric ( P constant) Molar specific heats of an ideal gas For a particular process V P=nR T p V=nR T (pV)=nR T Pf.Vf – Pi.Vi = nR T Cv = f/2*R Cp = (f+2)/2 * R Chapter Isochoric ( V constant) Isobaric ( P constant) State converting of an ideal gas Isothermal ( T constant) Physics2 Final Exam Adiabatic ( Q = ) Eint=Q-W=nCv T (J) Heat and first law of thermodynamics Change in entropy Heat : Q = nC T (J) Cv or Cp S=mc(lnT2-T1) Second law of thermodynamics S≥0 Isochoric ( V constant) Entropy in ideal gas Isobaric ( P constant) Chapter Isothermal ( T constant) Adiabatic(Q=0) S=0 Cooling or heating Phase change Entropy in liquid and solid Unchanging T-process Q = mc T When phase change : Q = Lm