Linked Questions
19 questions linked to/from What is the difference between ∆G and ∆G°?
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What is the difference between ΔG and ΔG "with an o on top"? [duplicate]
What is the difference between $\Delta G$ and $\Delta G^\circ$? I couldn't figure it out.
Ex:
$\Delta G^\circ = -RT\ln K$
$\Delta G = \Delta G^\circ + RT \ln Q$
What is the difference, is it that $\...
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Is there an agreement for a specific temperature referred to in the context of standard Gibbs energy? [duplicate]
I found an exercise in Physical Chemistry by Atkins et al, 8th edition, page 235 that I found confusing. The question is as follows.
"7.2(b) Molecular bromine is 24 per cent dissociated at 1600 K ...
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Addition of hydrogen bromide to 1,3-butadiene: thermodynamic and kinetic control
The reaction of one equivalent of hydrogen bromide with 1,3-butadiene gives different products at under different conditions:1
The addition of hydrogen chloride also gives rise to similar products.2 ...
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Is the Gibbs standard free energy always constant?
I am a biochemistry student and we are learning about thermodynamics. Is the Gibbs standard free energy for a reaction always constant? The equation below suggests that it changes with temperature:
$$...
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What is the difference between ΔG and ΔrG?
Consider the reaction
$$\ce{A -> B}$$
The reaction Gibbs free energy, $\Delta_\mathrm{r} G$ is given by the following equation
$$\Delta_\mathrm{r} G = \Delta_\mathrm{r} G^\circ + RT \ln Q$$
Now ...
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Derivation of van 't Hoff equation for temperature dependence of equilibrium constant
While I was reading about the usefulness of the quantity $\Delta H$, I found that it can be used to calculate the how the equilibrium constant varies with temperature. How can this be done?
Does it ...
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If change in free energy (G) is positive, how do those reactions still occur?
I was doing a couple of problems for homework:
Calculate $K_\mathrm{sp}$ of $\ce{AgI}$ at $55.0\ \mathrm{^\circ C}$
Calculate $K_\mathrm{b}$ of $\ce{NH3}$ at $36.0\ \mathrm{^\circ C}$
I have to use ...
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Calculating ΔG at the extremes of reaction extent
This question follows on from a great post on comparing $\Delta_\mathrm{r} G^{\circ}$ to $\Delta_\mathrm{r} G$ answered here
The G vs ξ graph that is used in the answer is an excellent tool to ...
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Do I use the Nernst equation when the concentrations of electrolyte in both half cells are equal?
I'm doing a chemistry report, and for my experiment I investigated the amount of voltage produced by different half cells in a voltaic cell.
However, I tested them under nonstandard conditions as ...
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Change in standard Gibbs energy is always zero?
So I have this statement from our professor :
We have $\Delta G^\circ = -RT\ln K$ and under standard conditions the activities of all substances in the reaction is $1$ ($a=1$), therefore $\Delta G^\...
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Gibbs free energy in standard state vs. equilibrium
I have a problem with the definition of the standard Gibbs energy and its connection to the equilibrium constants.
I think, that I've basically understood what the different equation mean but there ...
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Temperature in the Gibbs Free Energy equation
My professor gave us 2 different ways to calculate this problem. I did it using the Clausis-Clapeyron equation.
However, I don't quite get the second method because I thought that if the change in ...
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Gibbs Free Energy Notation
What's the difference between $G$, $\Delta G$, $\Delta G^\circ$, and $\Delta_\mathrm r G^\circ$?
I've seen the first two used interchangably, and seen $G$ specifically referred to as change in Gibbs ...
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How come ∆G ≤ 0 is used for spontaneity in electrochemistry, not ∆G ≤ W(other)?
The spontaneity condition for a system at constant temperature and pressure in which the only type of work accomplished is of the $pV$ type can be expressed as:
$$\Delta G\le0\tag1$$
In case of ...
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What does "heat is evolved at standard-state conditions" mean?
When $\pu{0.539 g}$ of $\ce{Na(s)}$ reacts with excess $\ce{F2(g)}$ to form $\ce{NaF(s)}$, $\pu{13.3 kJ}$ of heat is evolved at standard-state conditions. What is the standard enthalpy of formation ($\...
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