delta S

[katherinemurk 2B]

under what conditions does delta S = 0

[Vy Lu 2B]

Delta S (surroundings) is zero under free expansion; delta S (universe) is zero under reversible conditions and equilibrium; delta S (system) should be zero when there is no transfer of heat from and to the system and when the temperature and volume are constant in the system.

[Sarah Fatkin 4I]

Delta S of the system equals zero when there is no heat entering the system, because detla S = q(reversible)/T.

[JiangJC Dis2K]

For a system at equillibrium, the total delta s equals zero. For n irreversible expansion, given that there is no effect on the surroundings, delta s system equals delta s total.

[Ian Marquez 2K]

Like the replies above, delta S of the universe, or when negative delta S of the system is equal to delta S of the surroundings, is 0 when the reaction is at equilibrium and is reversible. Also, delta U would be 0.

[Ashe Chen 2C]

when q=0, or in free expansion.

[Niveda_B_3I]

The change in entropy would be zero when the heat transferred into or out of the system is 0.

[Jonny Schindler 1A]

When volume is constant, changes in pressure/temperature result in a change in entropy