3 Thermal Flashcards
temperature, T [K]
average KE of particles in an object
thermal energy
total KE of particles in an object
heat, Q [J]
ENERGY TRANSFER from one body to another due to TEMPERATURE DIFFERENCE
thermal equilibrium
same temperature → net heat flow = 0
A thermometer and electrical heater are inserted into small holes in an aluminum block. Suggest why the temperature of the block approaches a constant value.
net power supplied = net power loss
microscopic vs macroscopic
on the scale of particles vs people
ideal gas
- negligible volume of particles
- negligible intermolecular force
- negligible duration of collision compared to time in between + elastic collision
- move with random velocity + obey kinematics law
kinetic theory of gases
a model of the microscopic behaviour of gas particles that explains the macroscopic behaviour of the gas
internal energy, U [J]
total random KE + intermolecular PE
ideal gas has no intermolecular forces (PE=0) → U = KE!!
mole, n [mol]
amount of substance which contains as many elementary units as the amount of carbon atoms in 12g of carbon-12
Avogadro’s Constant, NA
the number of atoms in one mole (12g of carbon-12)
Specific Heat Capacityc [J kg-1 K-1]
energy needed;
to raise the temperature of 1kg of a substance;
by 1 K
evaporation vs boiling
evaporation: molecules escape from the SURFACE of the liquid into the atmosphere
boiling: molecules escape in the form of VAPOR from the BODY of the liquid
Specific Latent Heat of Fusion, l [J kg-1]
energy needed to convert 1kg of a substance from S → L at melting temperature
Specific Latent Heat of Vaporization, l [J kg-1]
energy needed to convert 1kg of a substance from L → G at boiling temperature
