Measuring delta G
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Measuring delta G
Is there any way to measure delta G? Or is the only way to calculate it using enthalpy and entropy?
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Re: Measuring delta G
No, there is no machine which we can use to measure DeltaG. The only way to get a value for deltaG is by calculating for it using
deltaG = deltaH - T(deltaS)
deltaG = deltaH - T(deltaS)
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Re: Measuring delta G
In problems dealing with multiple reactions, there are values in the appendix giving the standard Gibbs free energy for various reactions, which will be used like with standard enthalpy calculations.
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Re: Measuring delta G
Calculate deltaG by using standard enthalpy of formation and standard entropy values of R and P. So delta G =deltaH-Tdelta S.
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Re: Measuring delta G
Since we cannot measure ΔG directly, we use equations with values that we can measure to calculate ΔG.
We can measure equilibrium concentrations to calculate the equilibrium constant K, so we can calculate ΔG using K from measured concentrations:
ΔGo = -RTlnK
If the system is not at equilibrium, we use:
ΔG = ΔGo + RTlnQ
We can measure equilibrium concentrations to calculate the equilibrium constant K, so we can calculate ΔG using K from measured concentrations:
ΔGo = -RTlnK
If the system is not at equilibrium, we use:
ΔG = ΔGo + RTlnQ
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