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Fayt Sarreal 1G
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Postby Fayt Sarreal 1G » Sun Jan 15, 2017 5:12 pm

What is the difference between the two? How does the energy exchange with the surroundings?

Josh Ku 3H
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Postby Josh Ku 3H » Sun Jan 15, 2017 5:43 pm

As mentioned in the course reader an isolated system is one where neither matter or energy can exchange with the surroundings.

The system can exchange energy with the surroundings through the transfer of heat. Substances at higher temperatures will have more energy, while things at lower temperatures will have less energy. In an open or closed system, heat is allowed to transfer between the system and the surrounding (e.g. a cold pack) as the system can be freely cooled or heated by its surrounding. An isolated system is one that prevents this heat exchange via some sort of insulation such as a sealed insulated test tube or a sealed thermos bottle.

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Postby MayaKhalil_1L » Sun Jan 15, 2017 5:46 pm

In a closed system, matter cannot be exchanged between the system and the surroundings but energy can. A good example is a light bulb, physically nothing can go in or leave the bulb, but electricity goes in to power it and it gives off light and heat. In an isolated system, nothing can be transferred between the system and its surroundings. Think of a thermos; it's insulation is intended to keep heat from escaping.
Hope this helps!

Navi Sidhu 1F
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Postby Navi Sidhu 1F » Sun Jan 15, 2017 5:51 pm

In a open system, the system is not sealed and is not insulated.
In a closed system, the system is sealed but is not insulated.
In a isolated system, the system is sealed and insulated.

When a system is sealed, matter cannot be exchanged with its surrounding; when it's not sealed it can.
When a system is insulated, it cannot exchange energy with its surroundings; when it's not insulated it can.

Take a look at the figure in the middle of page 21 in the course reader.

I don't know if we've specifically discussed how energy exchanges with the system, but Wikipedia has an easy to understand explanation under the section "Mechanisms" on this webpage:

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