systems [ENDORSED]
Moderators: Chem_Mod, Chem_Admin
-
- Posts: 67
- Joined: Fri Sep 29, 2017 7:07 am
systems
regarding homework problem 8.1, why is mercury in a thermometer a closed system rather than isolated?
-
- Posts: 62
- Joined: Fri Sep 29, 2017 7:04 am
- Been upvoted: 2 times
Re: systems
The way a thermometer works is that mercury expands when it absorbs heat. This absorption of heat is responsible for mercury rising in a thermometer under warm conditions. Since energy can still be transferred, it is considered a closed system rather than an isolated one.
-
- Posts: 52
- Joined: Thu Jul 13, 2017 3:00 am
- Been upvoted: 1 time
Re: systems
Energy is transferred, but the amount of mercury (matter) is still the same. Closed systems are involved in only heat exchange with the surrounding.
-
- Posts: 50
- Joined: Fri Sep 29, 2017 7:04 am
- Been upvoted: 2 times
Re: systems
If a thermometer was an isolated system, it would not be able to interact with its surroundings, aka the mercury in the thermometer would not rise or fall according to different temperatures. Thus, we can rule out that a thermometer is an isolated system just on the principle that it works. Additionally, since the mercury is in a closed tube, we know that this must be a closed system as it is not open to its surroundings.
-
- Posts: 23858
- Joined: Thu Aug 04, 2011 1:53 pm
- Has upvoted: 1253 times
-
- Posts: 30
- Joined: Sat Jul 22, 2017 3:00 am
Re: systems
It's really easy to confuse isolated and closed systems but the key in this example is to recognize that the mercury is affected by the temperature outside, so there there is an exchange of energy in the form of heat between the contents of the system (mercury) and the surroundings.
Return to “Thermodynamic Systems (Open, Closed, Isolated)”
Who is online
Users browsing this forum: Google [Bot] and 11 guests