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HW #1 PART E

Posted: Sat Jan 20, 2018 4:20 pm
by Michelle Steinberg2J
Can someone please explain why mercury in a thermometer is a closed system?

Re: HW #1 PART E

Posted: Sat Jan 20, 2018 4:26 pm
by Andres Reynoso 1J
Mercury in a thermometer is a closed system because only energy can be exchanged with its surroundings. Matter cannot be exchanged within the system.

Here is a more detailed example for the thermometer's case:
A thermometer is placed under someone's tongue. The heat (energy) from their body (surroundings) is transferred to the thermometer (system). The volume of the mercury expands, but no mercury or any other substance (matter) enters or leaves the system.)

Re: HW #1 PART E

Posted: Sat Jan 20, 2018 4:30 pm
by Thuy-Anh Bui 1I
A closed system is one that can exchange energy but not matter with the surroundings. Mercury in a thermometer exchanges energy with its surroundings to rise and fall in the tube and indicate the temperature, but it does not leak and exchange matter. Hope this helps!

Re: HW #1 PART E

Posted: Sat Jan 20, 2018 4:47 pm
by Ashley Macabasco 2K
Mercury in a thermometer is an example of a closed system because the mercury itself is unable to leave the thermometer, but its energy is able to be exchanged with its surroundings (energy seen as heat). The transfer of heat is what makes the mercury leave in a thermometer rise or drop with heat causing mercury to rise. If it were an open system, then the amount of mercury itself would be able to escape out of the thermometer and if it were an isolated system then no heat would be able to reach the system.