1. By: Yong Yu Wen (33) 303

2. What is it? is the subject of the relation of heat to forces acting between contiguous parts of bodies, and the relation of heat to electrical agency.” Definition the concise definition of the subject was first given by a Scottish physicist, William Thomson in 1854 History thermodynamics concerns energy transfer to or from a thermodynamic system. a thermodynamic system is any collection of objects that is convenient to regard as a unit, and that may have the potential to exchange energy with its surroundings. Thermodynamic system

4. Laws of Thermodynamics system of laws that describe the transport of heat and work in thermodynamic processes claim that energy can be exchanged between physical systems as heat or work. claim the existence of a quantity named entropy

5. Laws of Thermodynamics have become some of the most important fundamental laws in physics and other sciences associated with thermodynamics four laws the zeroth law underlies the basic definition of temperature

6. Laws of Thermodynamics the second law states that the entropy of an isolated macroscopic system never decreases, or that perpetual motion machines are impossible the third law concerns the entropy of a perfect crystal at absolute zero temperature, and which implies that it is impossible to cool a system all the way to exactly absolute zero the first law mandates conservation of energy, and states in particular that the flow of heat is a form of energy transfer there have been suggestions of additional laws, but none of them have anything like the generality of the accepted laws, and they are not mentioned in standard textbooks

7. Zeroth law coined by Ralph H. Fowler in the 1920s the most fundamental of the four numbered laws of thermodynamics called the zeroth law because the need to state it explicitly was not understood until after the First, Second, and Third Laws had been named and become commonplace coined by Ralph H. Fowler in the 1920s the most fundamental of the four numbered laws of thermodynamics called the zeroth law because the need to state it explicitly was not understood until after the First, Second, and Third Laws had been named and become commonplace

8. Zeroth law generalization principle of the thermal equilibrium among bodies, or thermodynamic systems, in contact it results from the definition and properties of temperature a system is said to be in thermal equilibrium when its temperature does not change over time often claimed that we can define a temperature function or more informally, that we can "construct a thermometer." in the space of thermodynamic parameters, zones of constant temperature will form a surface, which provides a natural order of nearby surfaces

9. Zeroth law the temperature so defined may indeed not look like the Celsius temperature scale, but it is a temperature function nonetheless the dimensionality of a surface of constant temperature is one less than the number of thermodynamic parameters it is then simple to construct a global temperature function that provides a continuous ordering of states

10. First law an expression of the principle of conservation of energy states that energy can be transformed,but cannot be created or destroyed in any process in an isolated system, the total energy remains the same for a thermodynamic cycle the net heat supplied to the system equals the net work done by the system

12. First law formulated by saying that the change in the internal energy of a system is equal to the amount of heat supplied to the system, minus the amount of work done by the system on its surroundings

13. First law the first explicit statement of the first law of thermodynamics was given by Rudolf Clausius in 1850 “There is a state function E, called ‘energy’, whose differential equals the work exchanged with the surroundings during an adiabatic process."

14. First law the First Law clarifies the nature of energy it is a stored quantity which is independent of any particular process path if a system undergoes a thermodynamic cycle, whether it becomes warmer, cooler, larger, or smaller, then it will have the same amount of energy each time it returns to a particular state

15. First law mathematically speaking, energy is a state function and infinitesimal changes in the energy are exact differentials the first law can be expressed as the fundamental thermodynamic relation heat supplied to a system = increase in internal energy of the system + work done by the system increase in internal energy of a system = heat supplied to the system - work done by the system

16. First law example:

17. Second law an expression of the universal principle of decay observable in nature measured and expressed in terms of a property called entropy it stats that the entropy of an isolated system which is not in equilibrium will tend to increase over time, approaching a maximum value at equilibrium

18. Second law in short, heat can spontaneously flow from a higher-temperature region to a lower- temperature region, but not the other way around example: a cup of hot coffee left on a table eventually cools, but a cup of cool coffee in the same room never gets hot by itself entropy change dS of a system undergoing any infinitesimal reversible process is given by δq / T δq is the heat supplied to the system and T is the absolute temperature of the system

19. Second law the origin of the second law can be traced to French physicist Sadi Carnot's 1824 paper Reflections on the Motive Power of Fire which presented the view that motive power (work) is due to the flow of caloric (heat) from a hot to cold body (working substance)

20. Second law in simple terms, the second law is an expression of the fact that over time, differences in temperature, pressure, and chemical potential tend to even out in a physical system that is isolated from the outside world entropy is a measure of how much this evening- out process has progressed

21. Second law there are many versions of the second law, but they all have the same effect, which is to explain the phenomenon of irreversibility in nature

22. Third law a statistical law of nature regarding entropy and the impossibility of reaching absolute zero of temperature most common statement: “As a system approaches absolute zero, all processes cease and the entropy of the system approaches a minimum value.” in short, entropy is temperature dependent and results in the formulation of the idea of absolute zero

23. Third law developed by the chemist Walther Nernst, during the years 1906-1912, and is thus sometimes referred to as Nernst's theorem or Nernst's postulate an alternative version of the third law: “If the entropy of each element in some (perfect) crystalline state be taken as zero at the absolute zero of temperature, every substance has a finite positive entropy; but at the absolute zero of temperature the entropy may become zero, and does so become in the case of perfect crystalline substances. “ this law provides an absolute reference point for the determination of entropy the entropy determined relative to this point is the absolute entropy

24. Third law in simple terms, the Third Law states that the entropy of most pure substances approaches zero as the absolute temperature approaches zero

25. References en.wikipedia.org/wiki/Thermodynamics web.mit.edu/16.unified/www/FALL/thermodynamics/index.html www.taftan.com/thermodynamics/ www.shodor.org/unchem/advanced/thermo/