Different Kinds of Symptoms

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Sophie Roberts 1E
Posts: 61
Joined: Fri Sep 28, 2018 12:17 am

Different Kinds of Symptoms

Postby Sophie Roberts 1E » Thu Jan 31, 2019 4:02 pm

Can someone please give examples for open, closed, and isolated systems? I'm still kind of confused by the definitions of them all so I think examples would help me understand the concepts better. Thanks!

Chem_Mod
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Re: Different Kinds of Symptoms

Postby Chem_Mod » Thu Jan 31, 2019 4:08 pm

Open system is when both energy and matter can be exchanged between system and surroundings.
Ex: heating up something on the stove in a pot (without lid) --> heat can be transferred from the stove to the food. It's an open system, so matter can also be exchanged (perhaps steam from the liquid).

Closed system is when only energy can be exchanged between system and surroundings.
Ex: if you put a lid on the pot from the example above, heat can be transferred, but no matter can be exchanged. All the water molecules (from steam) are trapped.

Isolated system is when no energy or matter can be exchanged.
Ex: Thermos: You keep your drink warm because the heat is insulated (no heat can escape and thus no heat transfer). No matter is exchanged either since the lid is closed.

Alana Sur 3B
Posts: 61
Joined: Fri Sep 28, 2018 12:25 am

Re: Different Kinds of Systems

Postby Alana Sur 3B » Thu Jan 31, 2019 4:17 pm

So basically a system is identified by its interaction with its surroundings.

- An open system: Matter and energy can exchange with the surroundings.
Eg. A glass of water - The water can evaporate and the glass does not provide any insulation.

- A closed system: The amount of matter is fixed, but the energy can exchange with the surroundings.
Eg. An ice pack to treat injuries

- An insulated system: There is no contact with the surroundings.
Eg. Water in a thermos

Anita Wong 1H
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Re: Different Kinds of Symptoms

Postby Anita Wong 1H » Fri Feb 01, 2019 8:25 pm

open system: glass of tea evaporating
closed system: boba drink with the plastic seal
isolated system: calorimeter

LilyL1C
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Joined: Fri Sep 28, 2018 12:20 am

Re: Different Kinds of Symptoms

Postby LilyL1C » Fri Feb 01, 2019 8:36 pm

An open system is one that can exchange matter and energy with its surroundings. So for example, a beaker with some hot water in it is an example of an open system because the system is not insulated and the water will eventually cool down and evaporate.
A closed system is one that can only exchange energy with its surroundings. So for example, a beaker filled with hot water that has a lid on it is an example of a closed system because the amount of water will not change(it will not evaporate), but it will eventually cool down because the beaker is not insulated.
And an isolated system is one that can exchange neither energy nor matter with its surroundings. So for example, an insulated beaker with some hot water is an example of an isolated system. The water will not evaporate, and it will not cool down for quite some time.

amogha_koka3I
Posts: 62
Joined: Fri Sep 28, 2018 12:24 am

Re: Different Kinds of Symptoms

Postby amogha_koka3I » Fri Feb 01, 2019 9:51 pm

Is insulation and the lack of it also a good indicator of the type of system it is?

Simran Rai 4E
Posts: 58
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Re: Different Kinds of Symptoms

Postby Simran Rai 4E » Fri Feb 01, 2019 10:09 pm

Insulation only helps identify isolated systems. If there is no insulation you'd still have to determine whether the system was open or closed.


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