1. The 4 Laws of Thermodynamics pg.54
EQ: What are the laws of thermodynamics?
We will evaluate the laws of thermodynamics
I will evaluate a situation and explain how the 2nd law applies to it

2. The 4 Laws of Thermodynamics

3. The 0th Law: Equilibrium
When two objects are separately in thermodynamic equilibrium with a third object, they are in equilibrium with each other.

4. The 1st Law: Energy
Perpetual Motion Machine, a device that will run forever without any outside source of energy
Conservation of energy – energy is not created or destroyed, just transformed to other forms

5. The 2nd Law: Entropy

6. The 2nd Law: Entropy
Energy of all kinds in our material world disperses or spreads out if it is not hindered from doing so.

7. The 2nd Law: Entropy Limits the amount of heat to do work

8. The 2nd Law: Entropy Limits the amount of heat to do work
Evaporate - GAS
Steam Engine
Condense - LIQUID

9. The 2nd Law: Entropy Restricts the direction of heat transfer
If two objects are not the same temperature then:
Heat will always flow from high to low temperatures.
Hot object will decrease in temperature and
cold object will increase in temperature
until they are both the same temperature.

10. The 2nd Law : Entropy Entropy which establishes time’s arrow

11. The 2nd Law Entropy
Entropy is randomness. Which is more random? A or B?
A B

12. The 2nd Law Entropy
2nd Law of Therm. says that nature always goes from order to disorder.
A B

13. Can’t you just restack the bricks?
Entropy can be lowered by doing work on the system.
You can stack the bricks back up by hand.
By providing energy, you can drive chemical reactions backwards.
High entropy
Low entropy

14. The 2nd Law Entropy Stored energy = Less entropy (unnatural)
Work has to be done to have stored energy

15. The 2nd Law Entropy

16. The 2nd Law Entropy
On the large scale, the ice “looks” more disordered.
On the small scale, the solid phase severely limits where the molecules could be.
The ice crystal molecules (less entropy) are much more ordered than the free moving liquid water molecules (more entroopy).

17. In Conclusion: Heat Death
Eventually, all energy will be entropic.
Chemical reactions will burn themselves out.
Temperatures will equalize.
Matter and energy will be spread out evenly across the universe, and no more chemical or physical processes will occur.

18. The 3rd Law: Temperature

19. Closing Task