Convert Fahrenheit to Celsius

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(Celsius* 9/5)+32 = Fahrenheit

ZERO:Two systems each in thermal equilibrium with a
third system are in thermal equilibrium to each other.

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First Law of Thermodynamics: Conservation of Energy

Q = ΔU + W

The change in energy of a system is the amt of energy added minus the energy spent doing work.

Q = heat

W = work

ΔU = change in internal energy

Second Law of Thermodynamics:

ΔS_total = ΔS_system+ΔS_surroundings > zero

The entropy of the universe increases in a spontaneous process and remains unchanged in an equilibrium process.

Third Law of Thermodynamics

It is impossible to reduce any system to absolute
zero in a finite series of operations. This means that a perfectly efficient heat engine
cannot be created.

Seebeck Effect:

conversion of temperature differences directly into electricity.
[image] Thermocouples measure T_difference between probe and voltmeter

Peltier Effect

calorific effect of an electrical current at the junction of two different metals.

heat is evolved at the upper junction (at T2), and absorbed at the lower junction

Joule-Thomson Effect:

gas allowed to expand = increased PE implies Decreased KE & Temp

[image]Describes Temp Change of a gas or Liquid forced thru a valve and then allowed to expand.

Joule-Thomson Effect:

@ room Temp, Temp of gases does what upon expansion?

Joule-Thomson Effect:

@ room Temp, Temp of gases decreases upon expansion.

(except hydrogen, helium, and neon)

Calorie: unit of heat energy

• Calorie- amt of heat required to raise T of one gram of water from 14.5-15.5 Celsius

Specific Heat:

# of calories to raise T of 1g of substance by 1 Celsius