6.2: Thermal Physics Flashcards
What is internal energy?
-The sum of the randomly distributed kinetic energies and potential energies of the particles in a body
How can internal energy be increased?
-By heating the system
-By doing work on the system
How do you convert from degrees centigrade to kelvin?
-Tk=Tc+273.15
How does internal energy change during a change of state?
-Kinetic energies do not change
-Potential energies change
-So the overall internal energy changes
What are the numerical constants for an ideal gas?
-Avogadro’s constant(Na)=6.02x10^23
-Molar gas constant(R)=8.31
-Boltzmann’s constant(K)=1.38x10^-23
What is the work done for an ideal gas?
-Energy=Pressure*change in volume
What are the ideal gas equations?
-p.V=n.R.T
-p.V=N.k.T
Where:
n= no of moles
N=no of molecules
R=molar gas constant
k=Boltzmann’s constant
T=temperature(kelvin)
p=pressure
V=volume
What is absolute zero?
- A temperature of zero kelvin at which the energy of a particle is a minimum
What is the pressure law?
-Pressure is proportional to temperature
-As long as volume and number of moles is constant
What is Boyle’s law?
-Pressure is indirectly proportional to the volume
-As long as temeprature and number of moles is constant
What is Charles’s law?
-The volume is proportional to the temperature
-As long as pressure and number of moles is constant
What is specific latent heat?
-The amount of energy required to change the state of 1kg of a substance without changing its temperature
What is the equation for specific latent heat?
-Energy=mass*specific latent heat
What is specific heat capacity?
-The amount of energy required to raise the temperature of 1kg of a substance by 1 degree kelvin
What is the equation for specific heat capacity?
-Energy=mass * specific heat capacity * change in temperature
What is the kinetic energy of an ideal gas?
-Equal to the internal energy
-Equals (1/2)mv^2 where v=Crms
-Equals (3/2)kT
Where:
m=mass
v=velocity
k=Boltzmann’s constant
T=temperature(kelvin)
What are the assumptions for an ideal gas?
-Collisions are elastic
-Obeys the ideal gas laws
-Motion of particles is random
-Volume of particles is negligible
-Time for collisions is instantaneous
-Obeys Newton’s laws of motion
What are the masses for an ideal gas?
-Mass=mass of one mole * number of moles
-Mass=mass of one molecule * number of molecules
What is Brownian motion?
-The idea that very small objects have random motion in a liquid/gas due to random bombardment by molecules
-This movement is fractionally more on one side so a force will push for an instant as net force shifts directions
-This causes a random motion
Information that can’t be put on flashcards
-Kinetic theory and its equations
