AP Physics 2 - Temperature and Kinetic Theory

Molecular Mass/atom mass

relative masses of atoms and molecules

Unified atomic mass unit

1u=1.6605x10^27kg

Temperature

average kinetic energy of the particles within a substance

thermometer

An instrument used to measure temperature

Fahrenheit

°F=9/5°C+32

Kelvin(absolute scale)

K=°C+273

Celcius

°C=5/9(°F-32)

Thermal Equilibrium+zeroth law of thermodynamics

Refers to the property of a thermodynamic system in which all parts of the system have attained a uniform temperature which is the same as that of the system's surroundings.

linear expansion

L = L0 (1 + αΔ T )

coefficient of expansion

the length change per unit of length/per degree of temperature

volume expansion

ΔV = ßVΔT

coefficient of volume expansion

The fractional change in volume per degree change in temperature.

Boyle's Law

if temperature of a gas is held constant, the volume varies inversely with the pressure
PV=constant

Charles's Law

volume of a gas held at a constant pressure is directly proportional to the absolute temperature

Gay-Lussac's Law

pressure exerted by gas held at a constant volume is directly proportional to the absolute pressure

Ideal Gas Law

PV=nRT

universal gas constant

R=8.314 J/molK

Avogadro's Number

6.02x10^23

Avogadro's hypothesis

Equal volumes of gases at the same temperature and pressure contain equal numbers of particles

ideal gas law

PV=NkT

Boltzmann's constant

k=R/NA=1.38 x 10^-23 K/K

KE=3/2kT

the average translational kinetic energy of molecules in random motion in an ideal gas is directly proportional to the absolute temperature of the gas

Root Mean Square Speed

square root of average of the squares of the magnitudes of the velocities of the molecules in a gas
v rms=√(3kT/m)

Critical Temperature

temperature where phase change occurs

Triple Point

three phases can exist together in equilibrium

Evaporation

liquid to gas

Condensation

gas to liquid

Boiling Point

temperature of liquid rises to the point at which vapor pressure inside bubbles equals or exceeds the external air pressure