Standard State

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Thu Uyen Tran 1B
Posts: 31
Joined: Fri Sep 29, 2017 7:05 am

Standard State

Postby Thu Uyen Tran 1B » Sun Jan 14, 2018 10:04 pm

When solving for standard enthalpy, everything must be balanced and in its standard state in the reaction. How can we determine if something is in its standard state or not? Also what should we do if something is in fact not in its standard state?

Jason Liu 1C
Posts: 52
Joined: Fri Sep 29, 2017 7:04 am

Re: Standard State

Postby Jason Liu 1C » Sun Jan 14, 2018 10:14 pm

Something is in its standard state when one mole of it is being produced. You can put something into its standard state by dividing both sides of the chemical equation by however much you need to make the product one mole.

Julian Krzysiak 2K
Posts: 49
Joined: Fri Sep 29, 2017 7:07 am

Re: Standard State

Postby Julian Krzysiak 2K » Sun Jan 14, 2018 10:24 pm

Elements are in their standard state when they are in their most stable phase at the temperature of interest, which is usually 25 Celsius, while exposed to a constant pressure of 1 atm (They must also be 1 mole if they are a solution). So you can look at a periodic table at 25 C. and check the phases, unless the problem specifically states the reaction to be occurring at another temperature.

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