Chapter 14 and 15 - Thermal Physics And Ideal Gases Flashcards
0 degrees celsius in kelvin
273
What happens when two objects with different temperatures are near each other?
Thermal energy moves from the hotter object to the colder object
What is specific heat capacity?
The energy required per unit mass to change the temperature by 1K
What is specific latent heat?
The energy required to change the state per unit mass while at a constant temperature.
What is specific latent heat of fusion?
The energy required to change a substance from solid to liquid.
What is the specific latent heat of vaporisation?
The energy required to change a substance from liquid to gas.
What are the five assumptions made in the kinetic model?
The atom contains a large number of atoms or molecules moving in random directions at random speeds
The volume of the gas is negligible compared to the volume of the container
The collisions are perfectly elastic
The time of collisions is negligible compared to the time between collisions
Intermolecular forces and gravity negligible
The pressure of a gas is inversely proportional to…
Its volume
How does increasing the temperature of a gas affect the speed of the molecules?
The modal and r.m.s speed increases.
The distribution of speeds becomes more spread out.
What is the kinetic theory of gases?
A model used to describe the behaviour of atoms or molecules in ideal gases.
If the volume and mass of a gas remain constant, the pressure of an ideal gas is directly proportional to…
Its absolute temperature
The equation of state of an ideal gas is pV = nRT, state what each symbol means
p = pressure V = volume n = number of moles R = Molar constant T = Temperature(In kelvin)
Why is the root mean square speed used instead of the mean velocity for particles in a ideal gas?
As velocity is a vector, the velocities of each particle would cancel out and be 0.
The equation for the Boltzmann constant is k = R/N(subscript A), state which each symbol means
k = Boltzmann constant
R = Molar constant
N(subscript A) = Avogadro constant
What is the internal energy of a gas?
The sum of the kinetic and potential energies inside a gas. There is no electrostatic potential, between particles in a gas, so all of the energy is in the form of kinetic energy in the particles.
