derive Delta G=-T Delta S
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According to my book(Elements of Physical Chemistry by Atkins and de Paula, 5th ed.), ΔG=−TΔStotal is valid only for constant pressure and temperature.
According to my book(Elements of Physical Chemistry by Atkins and de Paula, 5th ed.), ΔG=−TΔStotal is valid only for constant pressure and temperature.Enthalpy is defined as H=U+PV. So, when pressure and volume both are not constant, ΔH=ΔU+Δ(PV). So, enthalpy can be defined even if the pressure is not constant.
According to my book(Elements of Physical Chemistry by Atkins and de Paula, 5th ed.), ΔG=−TΔStotal is valid only for constant pressure and temperature.Enthalpy is defined as H=U+PV. So, when pressure and volume both are not constant, ΔH=ΔU+Δ(PV). So, enthalpy can be defined even if the pressure is not constant.Now the criterion for spontaneity is that ΔStotal>0. But
According to my book(Elements of Physical Chemistry by Atkins and de Paula, 5th ed.), ΔG=−TΔStotal is valid only for constant pressure and temperature.Enthalpy is defined as H=U+PV. So, when pressure and volume both are not constant, ΔH=ΔU+Δ(PV). So, enthalpy can be defined even if the pressure is not constant.Now the criterion for spontaneity is that ΔStotal>0. ButΔStotal=ΔSsys−ΔHT
According to my book(Elements of Physical Chemistry by Atkins and de Paula, 5th ed.), ΔG=−TΔStotal is valid only for constant pressure and temperature.Enthalpy is defined as H=U+PV. So, when pressure and volume both are not constant, ΔH=ΔU+Δ(PV). So, enthalpy can be defined even if the pressure is not constant.Now the criterion for spontaneity is that ΔStotal>0. ButΔStotal=ΔSsys−ΔHTwhere T is the temperature of the surroundings. Now, if any heat enters the surroundings, the temperature of the surroundings does not change provided that the surroundings
are large. I think that due to this the temperature of the system has essentially to be the same or infinitesimally greater/lesser than the surrounding temperature as the heat transfer has to take place reversibly.
are large. I think that due to this the temperature of the system has essentially to be the same or infinitesimally greater/lesser than the surrounding temperature as the heat transfer has to take place reversibly.But now, as G=H−TSsys,
are large. I think that due to this the temperature of the system has essentially to be the same or infinitesimally greater/lesser than the surrounding temperature as the heat transfer has to take place reversibly.But now, as G=H−TSsys,ΔG=ΔH−TΔSsys.
are large. I think that due to this the temperature of the system has essentially to be the same or infinitesimally greater/lesser than the surrounding temperature as the heat transfer has to take place reversibly.But now, as G=H−TSsys,ΔG=ΔH−TΔSsys.Thus, from comparison of equations, ΔG=−TΔStotal. So, I did not need to specify that pressure is constant and why does my book do so?
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