Explanation on State Properties

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Ranger Saldivar 2D
Posts: 28
Joined: Fri Sep 25, 2015 3:00 am

Explanation on State Properties

Postby Ranger Saldivar 2D » Sun Jan 10, 2016 2:18 am

What exactly is the criteria that differentiates whether something is considered a state property or not. Also, based on work and heat not being state properties can the explanation on them being classified so due to it, "depending on the path taken" be elaborated on.

Mariam Ghattas 2L
Posts: 14
Joined: Fri Sep 25, 2015 3:00 am

Re: Explanation on State Properties

Postby Mariam Ghattas 2L » Sun Jan 10, 2016 2:39 am

an example of something that is not state property:
if we have 2 students leaving from CS 50 to go to Ackerman union, they have different routes. a student might go to the financial aid office before the final destination while the other student could go straight to Ackerman. the amount of heat and work exerted by both students will be different. the student who went to financial aid first will exert more energy and do more work (walking ). while the other student will exert less energy. this means that the final- initial will be different although both students shared the same starting point and ending point. here the path matters.
i hope that helped :)

JudithGonzalez_1G
Posts: 13
Joined: Fri Sep 25, 2015 3:00 am

Re: Explanation on State Properties

Postby JudithGonzalez_1G » Sun Jan 10, 2016 4:25 pm

Something is considered a state property when in order to calculate its enthalpy change, the pathway and details of the reaction are not necessary or not needed to known. It is simply calculated by where it began and where it ended.
For example, temperature is a state property because you take the final temperature minus the initial temperature in order to get the change in temperature, and you don't need to know how the temperature changed in between.
You don't need to know the pathway or details for pressure, volume, temperature, density or heat capacity.

Work and heat are not state properties because they need conditions in order to calculate the change, it is not just final minus initial, the process and conditions in between need to be take account of.


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