Work on System vs Surrondings


and

Moderators: Chem_Mod, Chem_Admin

505095793
Posts: 61
Joined: Fri Sep 28, 2018 12:25 am

Work on System vs Surrondings

Postby 505095793 » Sun Feb 10, 2019 4:02 pm

How does work change depending if the work is done on the system or the surroundings?

Alexandra Albers 1D
Posts: 61
Joined: Fri Sep 28, 2018 12:18 am

Re: Work on System vs Surrondings

Postby Alexandra Albers 1D » Sun Feb 10, 2019 4:06 pm

If a system is doing work on its surroundings (such as expanding volume against a piston), then work should be considered negative. If a system is having work done on it, then work is positive for the equation of internal energy (delta U).

Ryan Troutman 4L
Posts: 68
Joined: Fri Sep 28, 2018 12:22 am

Re: Work on System vs Surrondings

Postby Ryan Troutman 4L » Sun Feb 10, 2019 4:16 pm

If work is done ON the system, then work will be positive and internal energy will increase as a result. On the other hand, if work is done by a system (so expanding outward if you think of a piston), then work is negative and the internal energy of the system will decrease as a result. (Based on the equation deltaU = q + w)

WilliamNguyen_4L
Posts: 65
Joined: Fri Sep 28, 2018 12:28 am

Re: Work on System vs Surrondings

Postby WilliamNguyen_4L » Sun Feb 10, 2019 4:18 pm

If work is done on the system then the surrounding is putting energy into the system. The system would be gaining energy and the surroundings would be losing energy. If the system is doing work then energy is being put into the surroundings. The system would be losing energy and the surroundings would be gaining energy.


Return to “Calculating Work of Expansion”

Who is online

Users browsing this forum: No registered users and 3 guests