The Second and Third Laws of Thermodynamics

Surroundings

________: constitute the rest of the universe outside the system.

ΔSsurr

________ is also inversely proportional to temperature.

Standard entropy values

________ can be used to calculate the standard entropy change (ΔS°) for a process.

Second law of thermodynamics

________: all spontaneous changes cause an increase in the entropy of the universe.

absolute entropy

It is possible to determine the ________ of a substance.

System

________: the part of the universe that is of specific interest.

System

the part of the universe that is of specific interest

Surroundings

constitute the rest of the universe outside the system

Second law of thermodynamics

all spontaneous changes cause an increase in the entropy of the universe

Third law of thermodynamics

the entropy of a pure perfect crystalline substance at zero Kelvin is zero

Standard Entropies, S°

these values are for 1 mole of a substance at a pressure of 1 bar and a temperature of 298 K

ΔSuniverse > 0

for a spontaneous process

ΔSuniverse < 0

for a nonspontaneous process (spontaneous in the reverse direction).

ΔSuniverse = 0

for a process at equilibrium