1. Ideal gas
Assumptions
Particles that form the gas have no volume and consist of single atoms.
Intermolecular interactions are vanishingly small.

2. Ideal gas
Equations of state PV=NkT P= pressure V= volume N=number of particles of gas k= Boltzmann Constant= 1.38x10-23J/K K=Kelvin temperature

3. Ideal gas
Equations of state PV=nRT P= pressure V= volume n=number of moles of gas R= Universal Gas Constant= K=Kelvin temperature

4. Ideal gas
Avogadro’s number

5. Ideal gas
Relationship between Avogadro’s number, Universal Gas constant, and Boltzmann constant.

6. Kinetic –molecular theory
Many molecules are in a container and they behave like point particles.(No volume)
The molecules move around randomly, and obey Newton’s laws.
The only interactions that the molecules undergo are elastic collisions with each other and the walls of the container.

7. Kinetic –molecular theory
Pressure is a result of the molecules colliding with the walls of the container. As the number of molecules or thir average speed increases, the pressure increases.

8. Kinetic –molecular theory
Results of kinetic-molecular theory.

9. Kinetic –molecular theory
Results of kinetic-molecular theory.

10. Kinetic –molecular theory
Internal energy of an ideal monatomic gas..

11. Kinetic –molecular theory
Other gas laws – the amount of gas does not change

12. Laws of Thermodynamics
The first Law of Termodynamics – If U is the internal energy of a system, than DU=Q-W. If Q>0 System gains heat If Q<0 System loses heat If W>0 Work is done by the system If W<0 Work is done on the system

13. Laws of Thermodynamics
The first Law of Thermodynamics – If U is the internal energy of a system, than DU=Q-W

14. Table 18-1 Signs of Q and W
Q positive
System gains heat
Q negative
System loses heat
W positive
Work done by system
W negative
Work done on system

15. Figure 18-1 The Internal Energy of a System

16. Figure 18-2 Work and Internal Energy

17. Laws of Thermodynamics
At constant pressure, the work done by or on a system is W=PΔV The area under a PV curve represents work. If a process occurs at a constant volume, the work done during the process is 0.

18. Figure 18-5 A Constant-Pressure Process

19. Example 18-2 Work Area

20. Laws of Thermodynamics
Isothermal processes – these are processes that take place at a constant temperature. PV=constant

21. Figure 18-8 Isotherms on a PV Plot

22. Laws of Thermodynamics
Adiabatic processes – these are processes that take place without heat entering or leaving the system.

23. Figure 18-9 An Isothermal Expansion

24. Figure 18-10a An Adiabatic Process

25. Figure 18-10b An Adiabatic Process

26. Conceptual Checkpoint 18-2 Page 578 Which is the adiabatic curve?

27. Figure 18-14 A Comparison Between Isotherms and Adiabats