## The laws of thermodynamics

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J_Rodriguez_Dis2k
Posts: 25
Joined: Fri Sep 25, 2015 3:00 am

### The laws of thermodynamics

I'm very confused about the laws of thermodynamics. Can someone please explain to me what are the three laws regarding thermodynamics.

PriyaKohli3B
Posts: 31
Joined: Fri Sep 25, 2015 3:00 am

### Re: The laws of thermodynamics

Yes!
The first law states that energy cannot be created or destroyed.
The second law sates that the entropy of an isolated system not in thermal equilibrium will always increase.
The third law states that the entropy of a system approaches a constant value as the temperature approaches absolute zero.
The link below also explains the three very well!

Source: Boundless. “The Three Laws of Thermodynamics.” Boundless Chemistry. Boundless, 14 Oct. 2015. Retrieved 31 Jan. 2016 from https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/thermodynamics-17/the-laws-of-thermodynamics-123/the-three-laws-of-thermodynamics-496-3601/

Austin Hyun 1F
Posts: 26
Joined: Fri Sep 25, 2015 3:00 am

### Re: The laws of thermodynamics

So basically, the First Law of Thermodynamics states that energy cannot be created or destroyed; it is conserved during energy transfers or transformations. As the course reader describes on pg. 26, "the internal energy of an isolated system is constant."

The Second Law of Thermodynamics states that the entropy of an isolated system will increase over time, while the Third Law of Thermodynamics states that at absolute zero (0 K), a perfect crystal will have an entropy of zero (http://www.livescience.com/50942-third-law-thermodynamics.html). Therefore, based upon the premise of the Second Law, the actual occurrence of a zero entropy crystal is impossible.

I hope that helps clarify things!