Significance of open, closed, isolated

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Jessa Maheras 4F
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Joined: Fri Aug 02, 2019 12:16 am

Significance of open, closed, isolated

Postby Jessa Maheras 4F » Tue Feb 04, 2020 10:02 pm

I understand the difference between open, closed and isolated systems, but what is the significance of recognizing and understanding what type of system a reaction is when answering problems and doing calculations? Does the type of system affect what must stay constant in a reaction? What information does knowing the type of system give us?

Rida Ismail 2E
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Joined: Sat Sep 07, 2019 12:16 am

Re: Significance of open, closed, isolated

Postby Rida Ismail 2E » Tue Feb 04, 2020 10:47 pm

Well it is very important to know because you want to see what is naturally exchanged. In open both matter and energy is exchanged. In closed just energy is exchanged. And in isolated nothing is. The type of system definitely affects what stays constant.

Megan Kirschner
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Re: Significance of open, closed, isolated

Postby Megan Kirschner » Wed Feb 05, 2020 9:33 pm

Exactly- it helps you determine which variables are constant in an equation (and can thus be substituted for 0s).

Jialun Chen 4F
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Re: Significance of open, closed, isolated

Postby Jialun Chen 4F » Wed Feb 05, 2020 10:32 pm

For a closed system, heat can be exchanged but volume remains constant. An open system has constant pressure yet a changing volume. An isolated system has no energy exchange whatsoever (eg. bomb calorimeter).

Jocelyn Thorp 1A
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Re: Significance of open, closed, isolated

Postby Jocelyn Thorp 1A » Fri Feb 07, 2020 9:03 pm

Jialun Chen 4F wrote:For a closed system, heat can be exchanged but volume remains constant. An open system has constant pressure yet a changing volume. An isolated system has no energy exchange whatsoever (eg. bomb calorimeter).

exactly this! This information can be used to help solve problems. For example, for open systems, since pressure is constant (isobaric conditions), enthalpy is equal to the heat transferred (making the calculation much simpler).

Maika Ngoie 1B
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Re: Significance of open, closed, isolated

Postby Maika Ngoie 1B » Sun Feb 09, 2020 7:35 pm

It's important to spot the difference because it'll help better understand the relationship between the system and surroundings and to understand the corresponding variables for each system (i.e. open system=constant pressure, among others)

Ruby Richter 2L
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Re: Significance of open, closed, isolated

Postby Ruby Richter 2L » Mon Feb 10, 2020 10:14 am

So since the pressure is constant in an open system does that mean it is not constant in closed and isolated systems?

Jessa Maheras 4F
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Joined: Fri Aug 02, 2019 12:16 am

Re: Significance of open, closed, isolated

Postby Jessa Maheras 4F » Wed Feb 12, 2020 9:39 am

Jialun Chen 4F wrote:For a closed system, heat can be exchanged but volume remains constant. An open system has constant pressure yet a changing volume. An isolated system has no energy exchange whatsoever (eg. bomb calorimeter).


So, in an isolated system, if it has no exchange of energy, can work be done? What would the value of q be? Would q=0?

Jialun Chen 4F
Posts: 108
Joined: Sat Sep 07, 2019 12:16 am

Re: Significance of open, closed, isolated

Postby Jialun Chen 4F » Wed Feb 12, 2020 11:35 pm

Jessa Maheras 4F wrote:
Jialun Chen 4F wrote:For a closed system, heat can be exchanged but volume remains constant. An open system has constant pressure yet a changing volume. An isolated system has no energy exchange whatsoever (eg. bomb calorimeter).


So, in an isolated system, if it has no exchange of energy, can work be done? What would the value of q be? Would q=0?

Correct! q would be zero since the deltaU (internal energy) is zero, which we can also deduce that w=0.

Kishan Shah 2G
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Re: Significance of open, closed, isolated

Postby Kishan Shah 2G » Thu Feb 13, 2020 1:25 am

In my opinon. The most applicable scenario in which we would use our knowledge about closed, isolated, and open systems in when assessing whether there are changes in heat and work. For example since a bomb calorimeter is an isolated system there is no work done on the system.

Lizette Noriega 1H
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Re: Significance of open, closed, isolated

Postby Lizette Noriega 1H » Thu Feb 13, 2020 9:28 am

The status of the system helps you recognize the presence/absence of exchange in energy and matter, thus allowing you to understand the relationship between the system and its surroundings (and helps you solve the problems given).

Jessa Maheras 4F
Posts: 121
Joined: Fri Aug 02, 2019 12:16 am

Re: Significance of open, closed, isolated

Postby Jessa Maheras 4F » Sun Mar 15, 2020 7:15 am

Jialun Chen 4F wrote:
Jessa Maheras 4F wrote:
Jialun Chen 4F wrote:For a closed system, heat can be exchanged but volume remains constant. An open system has constant pressure yet a changing volume. An isolated system has no energy exchange whatsoever (eg. bomb calorimeter).


So, in an isolated system, if it has no exchange of energy, can work be done? What would the value of q be? Would q=0?

Correct! q would be zero since the deltaU (internal energy) is zero, which we can also deduce that w=0.


Alright great Julia Thank you!


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