Standard state

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Grace Han 2K
Posts: 33
Joined: Tue Nov 15, 2016 3:00 am

Standard state

Postby Grace Han 2K » Tue Jan 23, 2018 2:41 pm

How do you know if an element or compound is in its standard state? My notes says that while calculating standard rxn enthalpy, to make sure everything is in standard state and if it is not, take into account of phase change.

Britney Alvey 1B
Posts: 31
Joined: Fri Jun 23, 2017 11:39 am

Re: Standard state

Postby Britney Alvey 1B » Tue Jan 23, 2018 2:53 pm

The standard state of an element is the state it is in at 25 and 1 atm of pressure.

Posts: 32
Joined: Thu Jul 27, 2017 3:00 am

Re: Standard state

Postby RyanS2J » Tue Jan 23, 2018 3:00 pm

Some examples that might be helpful are that carbon in its standard state is graphite, and certain elements (H, N, O, F, Cl, Br, I) exist in their diatomic forms at standard state (H2, N2, O2, F2, etc.).

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