Thermodynamics the First Law

7vl (a) isolated (b closed (e) isolated id) open (e) closed if) open 

AV is negative because the air in the pump is compressed to a smaller volume work is then  

7 (a) The internal encrg increased by moi e than the amount of heat added. 

Therefore, the extra cnerg must have come from work done on the system. 

The energy change due to the work term, turns out to be negligible in f V -problem. 

Quantitative description of energy changes in physical (e.g., phase changes) and chemical 

A paddlewheel stirrer immersed in a liquid produces heat from mechanical work yielding a temperature rise in the liquid. 

A hot gas expanding in an insulated cylinder coupled to a flywheel produces mechanical work from heat and results in a temperature drop in the gas. 

Laws of thermodynamics reflected in the behavior of large numbers of atoms or molecules in a sample 

Link between the atomic level behavior and the behavior of bulk matter 

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Thermodynamics. The first law of thermodynamics, which states that energy can neither be created nor destroyed, dictates that the total energy entering an industrial plant equals the total of all of the energy that exits. Eeedstock, fuel, and electricity count equally, and a plant should always be able to close its energy balance to within 10%. If the energy balance does not close, there probably is a big opportunity for saving. 

In this case there is an increase of entropy in an irreversible process, whilst the energy remains constant. This result brings out clearly the independence of the two fundamental principles of thermodynamics, the first law dealing with the energy of a system of bodies, and the second law with the entropy. 

In thermodynamics the first law is often written in the form (see Section 2.13)... 

First Law of Thermodynamics The First Law of Thermodynamics states that the total energy of the universe is constant. 

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