1. AMALIA SHOLEHAH JURUSAN TEKNIK METALURGI FT – UNTIRTA THERMODYNAMICS

2. Overview General ChemistryPhysical Chemistry First Law: The internal energy of an isolated system is constant Zeroth Law: If two thermodynamics systems are in thermal equilibrium with a third, they are also in thermal equilibrium with each other First Law: The energy of an isolated system is constant. It implies that energy can never be created or destroyed, it can only change its form. For a system U = q + w ; Where (U) represents a change in internal energy, (q) is the change in thermal energy and (w) is the work done Second Law: A spontaneous change is accompanied by an increase in the total entropy of the system and its surroundings Second Law: Whenever a spontaneous event takes place it is accompanied by an increase in the entropy of the universe Third Law: For a pure crystalline substance, S = 0 at 0°K

3. Study of the patterns of energy change " thermo"  energy "dynamics"  the patterns of change Deals mainly with (A) energy conversion (B) the stability of molecules (C) direction of change

5. Laws of Thermodynamics They control interactions of everything in the universe - regardless of scale Classical physics is, from a certain perspective, entirely based on Newton's Laws of motion  only applicable in certain conditions Development of the Laws of Thermodynamics actually began thousands of years ago The largest advancements in developing the Laws of Thermodynamics occurred in the mid-1800s  Joule’s experiment  First Law of Thermodynamics

6. Not long after  Clausius theory  Second Law of Thermodynamics Around 1906  Nernst theory  Third Law of Thermodynamics

7. State of a System System  physical universe that is under consideration System is separated from rest of universe by Real / Imaginary boundary Surroundings  part of universe outside the boundary

8. Thermodynamics Properties Extensive properties  Depend on the size of the system  Ex : Volume (V), mass Intensive properties  Not depend on the size of the ystem  Ex : Pressure (P), Temperature (T), density

9. Thermodynamics Process P – V conjugate pair  transfer of mechanical or dynamic energy as the result of work  Isobaric process  occurs on constant pressure (dynamically connected)  Isochoric / isometric process  occurs on constant volume (dynamically insulated)

10. T – S conjugate pair  transfer of thermal energy as the result of heating  Isothermal process  occurs on constant temperature (thermally connected)  Isentropic process  occurs on constant entropy  Adiabatic process  no energy added or subtracted from the system by heating or cooling (thermally insulated)

11. State Variables (Thermodynamic Coordinates) When a system is at equilibrium  its state defined entirely by the state variable  not depend on history of system Ex : pressure (P), temperature (T), internal energy (U), enthalpy (H), enthropy (S), and Gibbs energy (G)

12. Zeroth Law “ If two thermodynamics systems are in thermal equilibrium with a third, they are also in thermal equilibrium with each other ” A B C

13. A system in thermal equilibrium is a system whose macroscopic properties (like pressure, temperature, volume, etc.) are not changing in time When two systems are in thermal equilibrium:  both of the systems are in a state of equilibrium,  they remain so when they are brought into contact, where 'contact' is meant to imply the possibility of exchanging heat, but not work or particles

14. If a fluid is in thermal equilibrium with another system:  it has only one independent variable  the macroscopic properties have certain values

15. Isotherm Plot

16. Boyle’s Law  PV = f( θ ) Gay-Lussac’s Law  (PV) 1 (PV) 2 =  (  1,  2 ) (PV) 1 (PV) 2 = T1T1 T2T2 = T2T2 (PV) 1 T1T1

17. Ideal gas R = ideal gas constant (PV) T = nR