Thermodynamics

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THERMODYNAMICS CLASS NOTES:

We can feel heat and measure it. Heat always goes from high to low.

Thermo: heat

Dynamics: Moving or changing.

Thermodynamics: Concerned with the movement of thermal energy. Heat is energy on the move.

The transfer of energy from a warmer object to a cooler object.

Difference between heat and temperature: Heat represents the movement or transfer of thermal energy, the standard unit of measure for energy is the joule (J). While temperature is a measurement of the average kinetic energy or molecular movement in an object or system. MOLECULES THAT HAVE MORE MOVEMENT HAVE MORE KINETIC ENERGY.

MEASURING TEMPERATURE ALLOWS US TO PREDICT IN WHICH DIRECTION HEAT WILL FLOW.

Heat can be transferred into electricity. Meaning that it can transfer from one object to another as well as energy.

1st Law: The amount of energy in the universe is a constant. Energy can be transferred from one substance to another or transformed into other forms of energy, but it cannot be created or destroyed.

2nd Law: Energy always disperses from a more usable form of energy to a less usable form .

THERMODYNAMICS DESCRIBE THE BEHAVIORS OF A SYSTEM.

Entropy: The measurement of energy dispersal

Heat cannot travel from a cool object to a warm object!

Dispersed energy is less useful for us.

A lot of heat = a lot of entropy

Absolute zero: the temperature at which all molecular motion stops and entropy is zero.

3rd Law: The entropy of a system at absolute zero is zero.

Dissolving generates heat

Direction of heat transfer

Cold is the absence of heat, a substance feels cold to us because it takes heat away from us.

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