Does AG´° determine whether a reaction is spontaneous? Why?

Biochemistry
9th Edition
ISBN:9781319114671
Author:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.
Publisher:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.
Chapter1: Biochemistry: An Evolving Science
Section: Chapter Questions
Problem 1P
icon
Related questions
Question

 Could you help me with this? I'm stuck on this question.

## Does ΔG°' determine whether a reaction is spontaneous? Why?

In the context of thermodynamics and chemical reactions, ΔG°' (the standard Gibbs free energy change) is a crucial metric for determining whether a reaction is spontaneous. 

### Factors Affecting Spontaneity
1. **Negative ΔG°' Value**: A reaction is considered spontaneous under standard conditions if ΔG°' is negative. This indicates that the process can occur without external input of energy.
2. **Temperature and Pressure**: Although ΔG°' is measured under standard conditions (298 K and 1 atm), the actual conditions in which the reaction occurs may affect the spontaneity.
3. **Concentration of Reactants and Products**: The actual Gibbs free energy change (ΔG) also depends on the ratio of the concentrations of products to reactants, which is not reflected in the standard state.

### Explanation
The spontaneity of a reaction is fundamentally tied to the Gibbs free energy change, which combines the system's enthalpy (ΔH) and entropy (ΔS) changes according to the formula:

\[ \Delta G = \Delta H - T\Delta S \]

Where T represents the temperature in Kelvin. A negative ΔG indicates that the free energy of the system decreases, allowing the reaction to proceed spontaneously. 

### Graphical Interpretation
*Although there are no graphs or diagrams presented in the text, a typical graphical representation would often show a plot of Gibbs free energy (ΔG) versus reaction coordinate to visualize the energy changes during the reaction pathway.*

In summary, ΔG°' is a key determinant of reaction spontaneity, but actual reaction conditions must be considered for a complete understanding.
Transcribed Image Text:## Does ΔG°' determine whether a reaction is spontaneous? Why? In the context of thermodynamics and chemical reactions, ΔG°' (the standard Gibbs free energy change) is a crucial metric for determining whether a reaction is spontaneous. ### Factors Affecting Spontaneity 1. **Negative ΔG°' Value**: A reaction is considered spontaneous under standard conditions if ΔG°' is negative. This indicates that the process can occur without external input of energy. 2. **Temperature and Pressure**: Although ΔG°' is measured under standard conditions (298 K and 1 atm), the actual conditions in which the reaction occurs may affect the spontaneity. 3. **Concentration of Reactants and Products**: The actual Gibbs free energy change (ΔG) also depends on the ratio of the concentrations of products to reactants, which is not reflected in the standard state. ### Explanation The spontaneity of a reaction is fundamentally tied to the Gibbs free energy change, which combines the system's enthalpy (ΔH) and entropy (ΔS) changes according to the formula: \[ \Delta G = \Delta H - T\Delta S \] Where T represents the temperature in Kelvin. A negative ΔG indicates that the free energy of the system decreases, allowing the reaction to proceed spontaneously. ### Graphical Interpretation *Although there are no graphs or diagrams presented in the text, a typical graphical representation would often show a plot of Gibbs free energy (ΔG) versus reaction coordinate to visualize the energy changes during the reaction pathway.* In summary, ΔG°' is a key determinant of reaction spontaneity, but actual reaction conditions must be considered for a complete understanding.
Expert Solution
steps

Step by step

Solved in 2 steps

Blurred answer
Knowledge Booster
Medical terminologies
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biochemistry and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Biochemistry
Biochemistry
Biochemistry
ISBN:
9781319114671
Author:
Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.
Publisher:
W. H. Freeman
Lehninger Principles of Biochemistry
Lehninger Principles of Biochemistry
Biochemistry
ISBN:
9781464126116
Author:
David L. Nelson, Michael M. Cox
Publisher:
W. H. Freeman
Fundamentals of Biochemistry: Life at the Molecul…
Fundamentals of Biochemistry: Life at the Molecul…
Biochemistry
ISBN:
9781118918401
Author:
Donald Voet, Judith G. Voet, Charlotte W. Pratt
Publisher:
WILEY
Biochemistry
Biochemistry
Biochemistry
ISBN:
9781305961135
Author:
Mary K. Campbell, Shawn O. Farrell, Owen M. McDougal
Publisher:
Cengage Learning
Biochemistry
Biochemistry
Biochemistry
ISBN:
9781305577206
Author:
Reginald H. Garrett, Charles M. Grisham
Publisher:
Cengage Learning
Fundamentals of General, Organic, and Biological …
Fundamentals of General, Organic, and Biological …
Biochemistry
ISBN:
9780134015187
Author:
John E. McMurry, David S. Ballantine, Carl A. Hoeger, Virginia E. Peterson
Publisher:
PEARSON