"Standard conditions" vs. STP

Started by brandonh4
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brandonh4

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In one of TBR's worksheet, they identify "standard conditions" as 25C and 1 atm. I had always taken "standard conditions" to mean STP, which is 0C and 1 atm.

Can someone help set the record straight?
 
In one of TBR's worksheet, they identify "standard conditions" as 25C and 1 atm. I had always taken "standard conditions" to mean STP, which is 0C and 1 atm.

Can someone help set the record straight?

Standard conditions (1 atm & 25C) is dealing more with thermodynamic variables: enthalpy, entropy, and gibbs free energy. These are the conditions that these variables are initially measured at.

STP is 1 atm & 0C but again these values are based on non-thermodynamic variables.
 
Pretty much. A lot of data tables give you standard values at 25 C so that you don't have to make adjustments in a lab, which does lead to a certain level of ambiguity. I have no idea how well that's resolved in MCAT questions.