Final Exam!

Final Exam!

1. Chapter 14: Thermodynamics

   • Conservation of energy
     • Thermal equlibrium
       • Newtons Law of cooling:∆T/∆t=-1/t(T-T_2)
     • The energy that flows in a system is heat engery
       • SI unit: Joule (J)
         • 1 cal = 4.186 J
           • 1 Calorie= 1000 cal
   • Molecules properties : pressure, volume, and temperature
     • Fahrenheit, Celsius, Kelvin
       • Celsius To Kelvin: Tk = Tc + 273.15
       • Celsius to Fahrenheit: = 9/5Tc + 32
   • Zeroth Law of Therodynamics
     • Indicates that heat must always flow from high temperature to low temperature
     • If A & B and B &C are all in Thermal equilibrium so that (Ta=Tb) and (Tb=Tc) than (Ta=Tc)
   • Phases of Matter : solids, liquids, gas
     • Heat Capacity= Q/ΔT
     • Specific Heat:c = Q/mΔT
       • Assumes that system will not change phases
     • Calorimetry: determine the heat energy added to each system
       • Q=mcΔT
         • Q is positive when energy flows into a system, Q is negative when energy flows out of a system
     • When a phase change happens Latent Heat must be accoounted
       • Latent Heat of Fusion: amount of heat that must be added to change a substance from a solid to a liquid
         • To melt: Qmelt= mLfusion
         • To Freeze: Qfreeze= -mLfusion
       • Latent Heat of Vaporization: amount of heat that is associated with the phase change from a liquid to a gas
         • To Vaporize (boil)= Qvaporization = mLvaporization
         • To Condense: Qcondense = -mLvaporization

2. Chapter 15: Gases & Kinetic theroy

   • Newtons Law can be applied to dilute gasses.
     • Ideal Gas Law
       • Dilute gas: the spacing between molecules is much larger than the size of the individual molecules
         • Avogadro's Law
           • constant pressure and temperature
             • Volume is directly proportional to the # of molecules in the sample
         • Boyle's Law
           • Constant Temperature
             • the product of the pressure and volume is constant
         • Charles' Law
           • constant pressure
             • The change in temperature is proportional to the change in volume
         • Gay- Lussac's Law
           • constant volume
             • The changes in pressure are proportional to changes in temperature
       • PV=nRT
         • R= 8.31 J/mole K
         • n= # moles in gas present
       • PV=(N/Na)RT=N(R/Na)T
         • Boltzmann's constant (R/Na): Kb= 1.38x 10^-23 J/K
       • Specific Heat
         • ΔU=ΔQ=(3/2)NkbΔT
         • Heat capacity for 1 mole
           • Cv= ΔQ/ΔT=NaKb=(3/2)R
     • Impulse Theorem
       • ΔP= FΔT
         • P=(Nmv^2)/ 3V
         • PV=N(mv^2/3)
     • KE= (3/2)KbT
       • v=(3kbT/m)^-1/2
       • Mechanical energy= KE
         • KEtotal= N(KEtrans)=(3/2)NkbT
           • internal energy =U
             • U = (3/2)nRt
   • Molecular velocities, temperature and pressure
   • M= atomic mass
   • Avogardro's number: Na= 6.02 x 10^23 (the number of particles in a mole)
   • m (mass of an atom)=M/Na

3. Chapter 16: Thermodynamics

   • 1st Law
     • U= (3/2)Nkb or U=(3/2)nRT
     • The internal energy of an ideal gas depends only on the temperature and number of particles
     • ΔU=Uf-Ui=Q-w
       • -Q indicates heat flows out of a system
       • Positive Q indicates heat flows into a system
   • Thermal Resrvoir
     • Reservoir is much larger than the system to which it is connected
   • Work done by gas on a piston
     • W=FΔx
       • W=PAΔx=PΔ
         • The force and pressure is constant
   • Type of processes
     • Isobaric
       • Constant pressure
         • W=PΔV=P(Vf-Vi)
       • Compressing= -w
       • Expanding= w
     • Isothermal
       • W=nRTln(Vf/Vi)
       • -W =Pressure increases the Volume decreses
       • W= Pressure decreases the Volume increases