Physics and Math - Thermodynamics

MCAT Chapter 3

Zeroth Law of Thermodynamics

When one object is in the thermal equilibrium with another object and the second object is in equilibrium with the third object, then the first and third are also in equilibrium

Heat

transfer of thermal energy from a hotter object with higher temp to a colder object with lower temp

Thermal Equilibrium

no net heat flow between two objects in thermal contact

Third Law of Thermodynmaics

Entropy of a perfectly organized crtystal at absolute zero is zero

System

Portion of universe of intrest

Surroundings

Rest of universe not the system

Isolated Systems

Not capable exchanging matter or energy with their surroundings

Closed system

Capable exchanging energy, not matter, with surroundings

Open System

Exhcange both energy and matter with environment

State function

thermodynamic properties function of only current equilibrium state of system

Process functions

path taken to get from one state to another

First Law of Thermodyanmics

Change in the total internal energy of a system is equal to the amount of energy transferred in form of heat to the system, minus the amount of energy transferred from system in form of work

Second Law of Thermodynamics

Objects in thermal contact and not in thermal equilibrium will exchange heat energy such that the object with higher temp will give off heat energy to the object with a lower temp until both object have same temp and thermal equilbirum

Specific Heat

amount of heat energy required to raise one gram of a substance by one degree C or one unit K

Conduction

Direct transfer of energy from molecule to molecule through molecular collisions

Convection

Transfer heat by physical motion of a fluid over a material

Radiation

Transfer of energy by electromagnetic waves

Isothermal

constant temp, no change in internal energy

Adiabatic

No heat exchange

Isobaric

Occur at constant pressure

Isovolumetric

No chagne volume, no work accomplished

Entropy

measure of spontaneous dispersal of energy at specific temp