All Questions
Tagged with free-energy heat
10
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3
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Definition of Gibbs Free Energy and its interpretation [closed]
RELATIONSHIP BETWEEN $\Delta G$ & $W_\mathrm{non-PV}$
$dU = dq + dw_\mathrm{py} + dw_\mathrm{non-PV}$
for reversible process at constant T & P
$dU+pdV-TdS = dw_\mathrm{non-PV}$
$dH-TdS = dw_\...
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2
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Understanding the Role of Gibbs Free energy and Enthalpy as the energy required to drive a reaction
I was looking at the enthalpy change for water-splitting reaction:
$$ \Delta H^o_R = [\Delta H^0_{H_2(g)} +\frac{1}{2}\Delta H^0_{O_2(g)}]-\Delta H^0_{H_2O(l)} = \pu{285.83 kJ/mol}$$
According to ...
- 265
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Enthalpy and Bond Energy Sign Convention
I read that a negative enthalpy of formation means an exothermic reaction. Does that mean this reaction is true? The enthalpy of formation for $\ce{H_2O}$ is -285.8 kJ/mol.
$$\ce{2H2(g) + O2(g) -> ...
- 101
11
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2
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Can single molecules of C and O2 react in isolation, and if so how will momentum be conserved?
I am trying to figure out how is it possible to reconcile the reality of exothermic reactions, which means that kinetic energy is transferred to (heats) the surrounding matter, with the principle of ...
- 147
1
vote
1
answer
137
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Gibbs–Helmholtz equation
The Gibbs–Helmholtz equation was developed in the 1870's, while Nernst's heat theorem was developed in the early $20^{th}$ century (according to google/wikipedia). Nernst's heat theorem tells us that ...
- 189
3
votes
1
answer
2k
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Change in heat of photosynthesis
Consider a plant that uses the energy it receives from the sun to do work (to undergo photosynthesis) to produce glucose. The minimum amount of work this plant can do to produce 1 mole of glucose is ...
-1
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1
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Calculate Heat of Atomisation [closed]
What is heat of atomisation of P4O6(s) Given heat of sublimation of P4O6 is x kJ/mol & P–O bond energy is y kJ/mol.
What is heat of atomisation of P4O6(s) Given heat of sublimation of P4O6 is x ...
7
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2
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Does Gibbs free energy of formation always equal zero for elements in standard state?
I was looking through the appendix in my chemistry textbook when I noticed that every compound that had a $\Delta H_f$ of zero also had a $\Delta G_f$ of zero. So of course the compounds that have a $\...
6
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2
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Heat Capacity temperature dependence and Gibbs energy
I got this problem in school as a tool to get ready for International Chemistry Olympiad, but I have some problems with this challenge.
So, the problem is to calculate as precise as possible the Gibbs ...
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3
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1
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Is the activation barrier of a reaction related to the free energy or heat of formation of its reactants?
The energy barrier for activation appears in the derivation of a bimolecular reaction through collision or transition state theory, but it seems that from looking at diagram such as this one it seems ...
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