Thermal Physics Flashcards
(30 cards)
What is heat?
The sum of the kinetic energies of the particles in a system
What is temperature?
The average kinetic energy of the particles in a system
What is internal energy?
The sum of all of the kinetic and potential energies of the particles in a system
For a monatomic/ideal gas, internal energy the same as..
Heat
No chemical bonds/additional degrees of freedom so all kinetic energy must be translational (i.e. heat)
What happens to the total heat of a glass of water if ice cubes are added?
Total heat increases, beacuse the ice has heat
Why is the Celsius scale impractical for numerical equations?
It can become negative below a certain point
What is the SI unit for temperature?
Kelvins
What is absolute zero?
Temperature at which the volume/pressure of a gas becomes zero
How do you convert from degrees Celsius to Kelvins?
Add 273
What is thermal equilibrium?
When a body is absorbing and radiating thermal energy at the same rate
What is specific heat capacity?
The energy per unit mass per unit temperature change, without a changing phase
What is latent heat?
The energy per unit mass required to change from one phase to another without also causing a change in temperature
Define pressure
Force per unit area
What is atmospheric pressure at sea level?
Approximately 101 kPa or 1 atm
What is Avogadro’s constant?
The number of carbon atoms in 12 grams of carbon-12
What do experimental gas laws rely on?
Empirical observations
State Boyle’s Law
At constant temperature, the pressure and volume of a gas are inversely proportional
State Charles’ Law
At constant pressure, volume is directly proportional to absolute temperature
What does the Pressure Law state?
At constant volume, the pressure of a gas is directly proportional to absolute temperature
List the assumptions made for an ideal gas
- The gas contains a large number of particles
- The particles move rapidly and randomly
- The motion of the particles follows Newton’s laws
- All collisions are perfectly elastic
- There are no attractive forces between particles
- Any collisions between particles are instantaneous
- The particles have negligible volume compared to the volume of the container
What is the equation for work done by a gas?
W = p * ∆V
What is given by the product of pressure and volume?
Energy associated with pressure, calculated from the area under a pressure-volume graph
What is Brownian motion?
The random motion of certain particles when observed with a microscope
What does the kinetic model of matter state?
- Matter is made of tiny particles
- Particles are constantly moving
- Temperature is related to motion
- Particles interact with each other and their container
