There are three forms of energy:

1. Kinetic…the energy of motion…..

2. Potential….the energy of position

3. Electromagnetic…waves like light, xrays etc

All atoms and molecules attract each other

(but not equally); oppositely charged ions do also.

When attracting bodies are moved further apart the

Potential Energy increases.

When attracting bodies (atoms, molecules or

oppositely charged ions) move closer together the Potential Energy

decreases.

1. All molecules and atoms attract each other

The aftractions are not all equal

Mercury on glass

Water on glass

Mercury on wax

Water on wax

Not a movie

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1.All molecules and atoms attract each other

2.When atoms and molecules get closer together the Potential Energy gets smaller.

3.When atoms and molecules get further apart the Potential Energy gets larger.

PE

PE

KE = 1/2 Mass x (Velocity) 2

GAS

Heat energy is Kinetic Energy

The Law of Conservation of Energy

Energy is never destroyed; it just changes forms. (JUST CONSIDER POTENTIAL AND KINETIC )

PE + KE = CONSTANT

Example: 5 + 5 = 10 6 + 4 = 10 8 + 2 = 10

If PE gets bigger then KE gets smaller

1/2 M V2

Kinetic Potential Electromagnetic

Heat

For now EM isleft out of the scheme.

Within each categoryWithin each categoryenergy can go from oneenergy can go from onebody to anotherbody to another

A C

B

Can include Mass: E= MC2Macroscopic KE

Microscopic KE

D

A and B C D

Can go fromone kind of potential toanother ieGravitation to Spring energy

PE results from attracting or repelling objects being near; changing the position changes the PE. In chemistry all atomsattract and the closer they get the less the PE and more stablethey are thus forming bonds.

It freezes and molecules get closer together…does it get hot or cold?

Shows how wax molecules get closer together when they “freeze” thus PE goes down! And heat is given off!

PE + KE = Constant

WATERWATER

KClO3 + C12H22011 ---- KCl + C02 + H20

A careful analysis shows that, for example, carbonand hydrogen are much closer to oxygen after RX.