Isolated System

[Emily Glaser 1F]

Is

delta U=0
q=0
w=0
delta H=0

in an isolated system?

[Salman Azfar 1K]

An isolated system means no energy or matter can flow in or out, so often that will be the case. So yea, in isolated systems w and q will both be zero and delta U is zero.

[Ramya Lakkaraju 1B]

This fact that delta U = 0 allows us to set q = -w and do other calculations involving heat and work.

[CalebBurns3L]

Yes, since no energy or matter would be flowing in or out with all of those values set to 0.

[Kevin Tabibian 1A]

Yes, but be careful determining whether a question is asking for the change in energy of the system or a reaction within the system. Because all those terms could very well not be equal to zero for to a reaction within an ideal bomb calorimeter. But the total energy of the bomb calorimeter will be unchanged.

[204932558]

Yes, as no heat or matter flows into the system or exits the system.