Open, Closed, and Isolated Systems
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Open, Closed, and Isolated Systems
Hi, can someone please go more in depth on the differences between each kind of system and give some examples?
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Re: Open, Closed, and Isolated Systems
An open system can exchange matter and energy with its surroundings and an example of this is the human body. A closed system has a set amount of matter but can exchange energy with the surroundings. An example of a closed system is an ice pack used to treat athletic injuries. An isolated system has no contact with its surroundings. For example, a system sealed inside rigid, thermally insulating walls such as hot liquid in a thermos. Hope that helps!
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Re: Open, Closed, and Isolated Systems
Additional question, what type if system is a constant pressure calorimeter?
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Re: Open, Closed, and Isolated Systems
I think a constant pressure calorimeter would be an example of an open system because the volume can change. (Open system=stuff can be added or removed from system). It shouldn't be a closed system because volume shouldn't change, and it definitely cannot be isolated.
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Re: Open, Closed, and Isolated Systems
I think a constant pressure calorimeter is an isolated system because in order to measure the heat of a reaction, the reaction must be isolated so that no heat is lost to the environment. This is achieved by use of a calorimeter, which insulates the reaction to better contain heat. Coffee cups are often used as a quick and easy to make calorimeter for constant pressure.
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Re: Open, Closed, and Isolated Systems
What about bomb calorimeters? (Mentioned in 8.1) What are they and why are they isolated systems?
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Re: Open, Closed, and Isolated Systems
If I understand correctly, a bomb calorimeter is a device used to calculate specific heat under the circumstances of constant volume. It does not allow the transfer of heat or matter, therefore, it is an isolated system.
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Re: Open, Closed, and Isolated Systems
Isolated systems do not allow any transfer of heat or matter. A bomb calorimeter is considered an isolated system because it prevents any heat from the reaction inside from escaping to the surroundings, and is closed so that no matter from the surroundings can enter or leave the system.
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Re: Open, Closed, and Isolated Systems
A constant pressure calorimeter gives enthalpy values (as the definition of enthalpy is heat at constant pressure).
A constant volume calorimeter is a bomb calorimeter. You can remember this because as the volume stays constant and a reaction (igniting oxygen) takes place, the pressure increases inside this volume and can explode.
The bomb calorimeter is an isolated system.
A constant volume calorimeter is a bomb calorimeter. You can remember this because as the volume stays constant and a reaction (igniting oxygen) takes place, the pressure increases inside this volume and can explode.
The bomb calorimeter is an isolated system.
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