- #1
davidbenari
- 466
- 18
First question is : why is ##\bigg(\frac{\partial \Delta H_{vap/fusion maybe something else} }{\partial T} \bigg)_p=\Delta Cp ## I can't wrap my head around that and nowhere other than my class can I find such an expression.
The other question is regarding the calculation of stuff (say H, S, G, A) during chemical reactions as (for example, enthalpy of a reaction):
##H_{reaction}=\Bigg(\sum \nu_i \Delta Hº\Bigg)_{products}- \Bigg(\sum \nu_i \Delta Hº\Bigg)_{reactants}##
Namely I don't get why adding Deltas ##\Delta## of formation (I'm excepting entropy here) will give the correct enthalpy of the reaction.
I have a very naive argument that defends this expression which I will give just to see what happens:
I imagine two mountains of different height. Here height is refers to the thermodynamic variable in question and its strictly a Delta with respect to the ground. If I have two states, my way to check the height between them is to substract one Delta from the other.
This sounds dumb though.
Any help would be nice. Thanks!
The other question is regarding the calculation of stuff (say H, S, G, A) during chemical reactions as (for example, enthalpy of a reaction):
##H_{reaction}=\Bigg(\sum \nu_i \Delta Hº\Bigg)_{products}- \Bigg(\sum \nu_i \Delta Hº\Bigg)_{reactants}##
Namely I don't get why adding Deltas ##\Delta## of formation (I'm excepting entropy here) will give the correct enthalpy of the reaction.
I have a very naive argument that defends this expression which I will give just to see what happens:
I imagine two mountains of different height. Here height is refers to the thermodynamic variable in question and its strictly a Delta with respect to the ground. If I have two states, my way to check the height between them is to substract one Delta from the other.
This sounds dumb though.
Any help would be nice. Thanks!
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