Calculating ∆G for the Formation of Phosphorus Trichloride

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To calculate the standard Gibbs free energy change (∆G) for the formation of phosphorus trichloride (PCl3) from its elements, the equation ∆G = ∆H - T∆S is used. The user has determined the enthalpy change (∆H) to be -725.2 kJ and the entropy change (∆S) to be 263.6 J/K. There is uncertainty about the appropriate temperature to use in the calculation, with the user considering 25 degrees Celsius as the reference. The discussion emphasizes the importance of using consistent units and clarifying the temperature when calculating ∆G. Accurate values for ∆H and ∆S are crucial for determining the feasibility of the reaction.
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Homework Statement

Calculate the value of Go for the formation of 1 mol of phosphorus trichloride from its constituent elements:

P2(g) + 3 Cl2(g) ---> 2 PCl3(g)



The attempt at a solution

I thought of trying delta G = delta H - T deltaS , but I'm lost on where to start.



Thank you
 
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* Calculate the value of ∆G for the formation of 1 mol of phosphorus trichloride from its constituent elements

Sorry, typed in Go instead of ∆G.

I figured out ∆H and ∆S already (not sure if it's correct)

∆H = -725.2 kJ
∆S = 263.6 J/K

but in the equation ∆G = ∆H - T∆S I'm not sure what the temperature is suppose to be. I got the thermodynamic quantities at 25 degrees Celsius, do I use that as T even though it doesn't state the temperature in the question?

Thanks
 
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