Enthalpy


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Megan Cao 1I
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Enthalpy

Postby Megan Cao 1I » Tue Feb 11, 2020 5:49 pm

What does the term "state function" entail? All I've seem to understand from it is that it's only dependent of its current calculated state and that you can add it's values. Other than that, what does "state function" mean?

jisulee1C
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Re: Enthalpy

Postby jisulee1C » Tue Feb 11, 2020 6:03 pm

A state function means that only the initial state and final state are needed to determine the value. I think Lavelle's example of how only the initial and final destinations matter when you hike a mountain and how the pathway you took is irrelevant explains conceptually what a state function is.

Gurmukhi Bevli 4G
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Re: Enthalpy

Postby Gurmukhi Bevli 4G » Sat Feb 15, 2020 3:56 am

The value of state functions are independent of pathways taken to reach their initial/final values. Since pathway becomes inconsequential, the quantity is only dependent on initial and final values.

Fiona Latifi 1A
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Re: Enthalpy

Postby Fiona Latifi 1A » Sat Feb 15, 2020 1:21 pm

Examples of state functions include density, internal energy, enthalpy, and entropy.

Daria Azizad 1K
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Re: Enthalpy

Postby Daria Azizad 1K » Sat Feb 15, 2020 9:58 pm

A state function relies on initial and final values, not the pathway taken.

Juana Abana 1G
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Re: Enthalpy

Postby Juana Abana 1G » Wed Feb 19, 2020 8:05 pm

The value of a state function is only dependent on the initial value and the final value.

Brandon Valafar
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Re: Enthalpy

Postby Brandon Valafar » Thu Feb 20, 2020 11:58 am

State functions are independent values regardless of the pathway to get to the final value. The quantity only matters based on the final and initial values, and not the pathway to get there.

Dan M -3E
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Re: Enthalpy

Postby Dan M -3E » Sun Feb 23, 2020 3:35 pm

Something being a state function means that the pathway by which the value arrived at its final value does not matter in the calculation of the value.

san_2F
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Re: Enthalpy

Postby san_2F » Sun Feb 23, 2020 4:00 pm

A state function is a property that states that the path that something takes is irrelevant, the only thing that matters is the final result or final state. d

Brandon Valafar
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Re: Enthalpy

Postby Brandon Valafar » Sun Feb 23, 2020 4:18 pm

A state function doesn't rely on the pathway taken, it only relies on the initial and final values.

Chris Charton 1B
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Re: Enthalpy

Postby Chris Charton 1B » Sun Feb 23, 2020 7:50 pm

State functions only depend on initial and final values, thus intermediate steps are irrelevant when calculating enthalpy or entropy.

Ivan Tadeja 1G
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Re: Enthalpy

Postby Ivan Tadeja 1G » Sat Mar 14, 2020 10:21 am

Fiona Latifi 1A wrote:Examples of state functions include density, internal energy, enthalpy, and entropy.


Could you also give examples of what would not be a state function?

Chris Charton 1B
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Re: Enthalpy

Postby Chris Charton 1B » Sat Mar 14, 2020 9:36 pm

Ivan Tadeja 1G wrote:
Fiona Latifi 1A wrote:Examples of state functions include density, internal energy, enthalpy, and entropy.


Could you also give examples of what would not be a state function?


Work is an example of a non-state (path) function

DominicMalilay 1F
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Re: Enthalpy

Postby DominicMalilay 1F » Sun Jan 24, 2021 11:11 pm

I like to think of it as the state function being something that doesn't concern how you got to where you got to, just where you ended up. In other words, the journey doesn't matter! Only the start and end places.

Gicelle Rubin 1E
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Re: Enthalpy

Postby Gicelle Rubin 1E » Sun Jan 24, 2021 11:42 pm

I know it's a bit repetitive hearing the same thing but a state function means that, in order to determine its value, we only need both the initial and final state.

305572629
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Re: Enthalpy

Postby 305572629 » Sun Jan 24, 2021 11:45 pm

State functions do not rely on the path taken to get from an initial to final value.

Sam Wentzel 1F 14B
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Re: Enthalpy

Postby Sam Wentzel 1F 14B » Sun Jan 24, 2021 11:46 pm

State function means that you basically only need to consider the final and initial values of that function when calculating changes. Think of it as a "state" function because you only really need to consider the initial and final "states" of the function.

Change = final value - initial value of state function

Queena Chu 3E
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Re: Enthalpy

Postby Queena Chu 3E » Sun Jan 24, 2021 11:54 pm

A state function is a property that is describing a particular state and doesn't depend on the path taken to reach this state.

Catherine Bubser 2C
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Re: Enthalpy

Postby Catherine Bubser 2C » Sun Jan 31, 2021 6:59 am

The path a state function has/ takes does not matter with regard to its final value.

Jerry_T
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Re: Enthalpy

Postby Jerry_T » Sun Jan 31, 2021 4:55 pm

Work is not a state function because it depends on the path taken whereas a state function such as enthalpy only depends on the final and initial states.

905409193
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Re: Enthalpy

Postby 905409193 » Sun Jan 31, 2021 5:59 pm

State function doesn't consider the path taken, instead it focuses on the final and initial.

James_Hankee_1C
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Re: Enthalpy

Postby James_Hankee_1C » Sun Jan 31, 2021 8:56 pm

A state function is independent of the path taken to establish value. State functions in thermochemistry include pressure, volume, temperature, enthalpy, internal energy, Gibbs free energy, and entropy.

Bryan Le 2K
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Re: Enthalpy

Postby Bryan Le 2K » Sun Jan 31, 2021 9:21 pm

Enthalpy is a state function. This means that it doesn't relate to the path that it takes to reach the final values. It only corresponds with the initial and final values.

Kandyce Lance 3E
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Re: Enthalpy

Postby Kandyce Lance 3E » Sun Jan 31, 2021 10:49 pm

Gicelle Rubin 1E wrote:I know it's a bit repetitive hearing the same thing but a state function means that, in order to determine its value, we only need both the initial and final state.



and then we also subtract final minus initial right?

Samir 3I
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Re: Enthalpy

Postby Samir 3I » Sun Jan 31, 2021 11:46 pm

Yes you subtract the initial state from the final to get the final value

jia207
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Re: Enthalpy

Postby jia207 » Mon Feb 01, 2021 7:42 pm

To get the final value, you would subtract the initial state from the final state.

DPatel_2L
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Re: Enthalpy

Postby DPatel_2L » Mon Feb 01, 2021 11:33 pm

The value is only based on the initial and final value


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