System vs Surroundings

Milena Aragon 2B
Posts: 60
Joined: Fri Sep 28, 2018 12:19 am

System vs Surroundings

I have a hard time determining what the system is in a reaction. Is there a way of easily identifying what it is or do we have to memorize that for certain examples one is the system and thus the other is the surroundings?

Nathan Tran 4K
Posts: 92
Joined: Fri Sep 28, 2018 12:16 am

Re: System vs Surroundings

Usually, the system is the actual thing we are dealing with in the question. For example, if we are looking at the piston and identifying characteristics like work, heat, etc., the piston is the system, while the surroundings is what is supplying heat or what the system is losing heat to or the surroundings is what does work on the piston or what the piston is doing work on. I would say it is usually very easy to identify what is the system based off the question if it is not already explicitly identified.

Jonathan Zhao 4H
Posts: 57
Joined: Fri Sep 28, 2018 12:26 am

Re: System vs Surroundings

Yes, the system vs. surrounding should not be something you have to memorize. As mentioned before, the system is simply the situation in question, such as a piston. Since the first law of thermodynamics states the conservation of energy, a change in energy of the system means a resultant change in surroundings to balance it out.

Posts: 35
Joined: Fri Sep 28, 2018 12:19 am

Re: System vs Surroundings

System vs. surrounding should be evident depending on the question that is given. It usually just determines whether a certain value is positive or negative in relation to the system at hand. For example, if the question states the surroundings gained x amount of energy, then energy left the system, so the energy change of the system would have to be negative while the surroundings would have a positive value in energy change.

Fanny Lee 2K
Posts: 73
Joined: Fri Sep 28, 2018 12:29 am

Re: System vs Surroundings

Simply, the system is the object you are observing and the surrounding is everything else.

Yiting_Gong_4L
Posts: 69
Joined: Fri Sep 28, 2018 12:25 am

Re: System vs Surroundings

system is the object, and surrounding is everything around it that can apply heat to it or lose heat.

Tony Chung 2I
Posts: 60
Joined: Fri Sep 28, 2018 12:19 am

Re: System vs Surroundings

The system is the thing that you're observing/looking at, while the surrounding is everything else.

Brian Chang 2H
Posts: 65
Joined: Fri Sep 28, 2018 12:17 am

Re: System vs Surroundings

The system is the "reaction" that you're observing, typically in a piston or some form of enclosed chamber. (Unless it's an open system)

The surroundings are just everything else.

Manav Govil 1B
Posts: 104
Joined: Sat Sep 07, 2019 12:19 am

Re: System vs Surroundings

The system is the area where the reaction is occurring. The surroundings are the outside of where the reaction is occurring. Think of the reaction happening in a beaker. If the reaction is endothermic, it requires energy to come to fruition. Therefore, it will take energy from the surroundings, or outside the beaker, making the beaker feel cool on the outside. If the reaction is exothermic, it will be releasing heat into the surroundings, making the beaker feel hot.

Yiyang Jen Wang 4G
Posts: 76
Joined: Wed Nov 21, 2018 12:18 am

Re: System vs Surroundings

“The system is the part of the universe we wish to focus our attention on. In the world of chemistry, the system is the chemical reaction. For example:

2H2 + O2 ---> 2H2O

The system consists of those molecules which are reacting.

The surroundings are everything else; the rest of the universe. For example, say the above reaction is happening in gas phase; then the walls of the container are part of the surroundings.”

https://www.chemteam.info/Thermochem/Sy ... dings.html

Minh Ngo 4G
Posts: 137
Joined: Thu Jul 25, 2019 12:17 am

Re: System vs Surroundings

System is the one that you are focusing on. In most cases, it is the chemical rxn

805097738
Posts: 180
Joined: Wed Sep 18, 2019 12:20 am

Re: System vs Surroundings

Jonathan Zhao 4H wrote:Yes, the system vs. surrounding should not be something you have to memorize. As mentioned before, the system is simply the situation in question, such as a piston. Since the first law of thermodynamics states the conservation of energy, a change in energy of the system means a resultant change in surroundings to balance it out.

so a piston would indicate that you are working with a closed system?

Kaylee Clarke 1G
Posts: 103
Joined: Fri Aug 30, 2019 12:15 am

Re: System vs Surroundings

the system is were the chemical reaction would usually occur. I don't recall Professor Lavelle mentioning needing to memorize systems and surroundings.

Esha Chawla 2E
Posts: 108
Joined: Thu Jul 25, 2019 12:17 am

Re: System vs Surroundings

Milena Aragon 2B wrote:I have a hard time determining what the system is in a reaction. Is there a way of easily identifying what it is or do we have to memorize that for certain examples one is the system and thus the other is the surroundings?

The system is where the reaction is actually occurring. The surroundings are everything else. The sum of the system and the surroundings make up the universe.

annikaying
Posts: 94
Joined: Sat Sep 14, 2019 12:16 am

Re: System vs Surroundings

The system is the actual reaction and the surrounding is everything else.