state functions
Moderators: Chem_Mod, Chem_Admin
-
- Posts: 103
- Joined: Wed Sep 30, 2020 10:01 pm
state functions
Why are heat and work not state functions? I'm having a little trouble understanding the definition of state functions.
-
- Posts: 104
- Joined: Wed Sep 30, 2020 9:41 pm
Re: state functions
Heat and Work are not state functions because they are dependent on the path used to go from the initial to final state. State functions by definition only depend on the state of the system, not the path used to get to that state. I hope this explanation was somewhat helpful!
-
- Posts: 107
- Joined: Wed Sep 30, 2020 9:35 pm
- Been upvoted: 1 time
Re: state functions
Hi! So a state function doesn't depend on the pathway to it's final answer (so if you remember the example about climbing the mountain); so because work and heat depend on whether or not the expansion is reversible or irreversible, so it is not a state function.
-
- Posts: 113
- Joined: Wed Sep 30, 2020 9:39 pm
Re: state functions
Heat is the flow of energy dependent on temperature difference and it is representative of all energy that has passed through two states. It is not a state function because you need to account for all the possible energy, not just the difference between Finland initial. Work is not a state function because it similarly depends on the pathway. The way I remember this is because a reversible pathway does a different amount of work than an irreversible pathway even if final and initial volume for both are the same.
-
- Posts: 104
- Joined: Wed Sep 30, 2020 9:54 pm
Re: state functions
Heat and work are not state functions because the depend on the pathway taken. For example though a change in the same amount of volume between a reversible and nonreversible expansion maybe be equivalent, the work differs between the reversible and nonreversible reaction.
-
- Posts: 100
- Joined: Wed Sep 30, 2020 9:45 pm
Re: state functions
Heat and work are not state functions as the value of heat depends on the pathway it takes. However, state functions really only rely on their initial values and their final values.
-
- Posts: 102
- Joined: Wed Sep 30, 2020 9:33 pm
- Been upvoted: 3 times
Re: state functions
Hi! Just wanted to share a quick tip that I learned in a UA session to remember the state functions.
When you're under Pressure or Depressed, you want to watch TV and get HUGS
The things bolded stand for:
Pressure
Density
Temperature
Volume
Enthalpy
Internal Energy
Gibbs free energy
Entropy
When you're under Pressure or Depressed, you want to watch TV and get HUGS
The things bolded stand for:
Pressure
Density
Temperature
Volume
Enthalpy
Internal Energy
Gibbs free energy
Entropy
Who is online
Users browsing this forum: No registered users and 6 guests