Thermal ⛆ Flashcards
Internal energy
Sum of all kinetic energies and potential energies of all its particles. The kinetic and potential energies of a body are randomly distributed
How is internal energy increased
- Increase temperature of the system
- Do work on the system to transfer energy to it
What happens when state of substance changes
Internal energy also changes due to potential energy of the system changing while the kinetic energy is kept constant
Amount of energy required to change temp of substance EQ
Q = mc△θ
Specific heat capacity of a substance
Amount of energy required to increase the temperature of a substance by 1 Celsius, without changing its state
Amount of energy required to change state of substance EQ
Q = ml
Specific latent heat of a substance
Amount of energy required to change the state of 1 kg of material without changing its temperature
1. SLH of fusion (solid to liquid)
2. SLH of vaporisation (liquid to gas)
Gas law experimental relationship
Describes the experimental relationship between pressure, volume and temperature for a fixed gas. Arose from observation and experimental in nature
- Boyles law
When temperature is constant, pressure and volume are inversely proportional
pV = k
- Charles’ law
When pressure is constant, volume is directly proportional to absolute temperature
V/T = k
- The pressure law
When volume is constant, pressure is directly proportional to absolute temperature
Kelvin scale
K = C + 273
Absolute zero (-273)
Lowest possible temperature and the temperature at which particles have no kinetic energy and the volume and pressure of a gas are zero
Ideal gas EQ (for n moles)
pV = nRT
Ideal gas EQ (for N molecules)
pV = NkT