Domanda del libro di testo
Calculate the percentage of isopropylcyclohexane molecules that have the isopropyl substituent in an equatorial position at equilibrium. (Its ∆G° value at 25 °C is -2.1 kcal/mol.)
1448
views
Ch. 5 - Alkenes: Structure, Nomenclature, and an Introduction to Reactivity • Thermodynamics and Kinetics
Bruice8th EditionOrganic ChemistryISBN: 9780135213711
Non è quello che usi tu?Cambia libro di testoScegli un libro di testo diverso
TOC.tableOfContents
- Ch. 1 - Remembering General Chemistry: Electronic Structure and Bonding31
- Ch. 2 - Acids and Bases: Central to Understanding Organic Chemistry84
- Ch. 3 - An Introduction to Organic Compounds: Nomenclature, Physical Properties, and Structure183
- Ch. 4 - Isomers: The Arrangement of Atoms in Space121
- Ch. 5 - Alkenes: Structure, Nomenclature, and an Introduction to Reactivity • Thermodynamics and Kinetics83
- Ch. 6 - The Reactions of Alkenes • The Stereochemistry of Addition Reactions175
- Ch. 7 - The Reactions of Alkynes • An Introduction to Multistep Synthesis119
- Ch. 8 - Delocalized Electrons: Their Effect on Stability, pKa, and the Products of a Reaction • Aromaticity and Electronic Effects: An Introduction to the Reactions of Benzene148
- Ch. 9 - Substitution and Elimination Reactions of Alkyl Halides212
- Ch. 10 - Reactions of Alcohols, Ethers, Epoxides, Amines, and Sulfur-Containing Compounds131
- Ch. 11 - Organometallic Compounds60
- Ch. 12 - Radicals90
- Ch. 13 - Mass Spectrometry; Infrared Spectroscopy; UV/Vis Spectroscopy62
- Ch. 14 - NMR Spectroscopy95
- Ch. 15 - Reactions of Carboxylic Acids and Carboxylic Acid Derivatives123
- Ch. 16 - Reactions of Aldehydes and Ketones • More Reactions of Carboxylic Acid Derivatives141
- Ch. 17 - Reactions at the Alpha-Carbon101
- Ch. 18 - Reactions of Benzene and Substituted Benzenes144
- Ch. 19 - More About Amines • Reactions of Heterocyclic Compounds49
- Ch. 20 - The Organic Chemistry of Carbohydrates80
- Ch. 21 - Amino Acids, Peptides, and Proteins57
- Ch. 22 - Catalysis in Organic Reactions and in Enzymatic Reactions35
- Ch. 23 - The Organic Chemistry of the Coenzymes—Compounds Derived from Vitamins1
- Ch. 28 - Pericyclic Reactions58
Tutti i libri di testo
Bruice 8th EditionCh. 5 - Alkenes: Structure, Nomenclature, and an Introduction to Reactivity • Thermodynamics and KineticsProblema 18b
Bruice 8th EditionCh. 5 - Alkenes: Structure, Nomenclature, and an Introduction to Reactivity • Thermodynamics and KineticsProblema 18bCapitolo 5, Problema 18b
Calculate ∆G° for the conversion of “axial” methylcyclohexane to “equatorial” methylcyclohexane at 25 °C.
Guida verificata passo dopo passo1
Step 1: Understand the problem. The question asks to calculate the Gibbs free energy change (∆G°) for the conversion of axial methylcyclohexane to equatorial methylcyclohexane at 25 °C. This involves using the relationship between ∆G°, equilibrium constant (K), and temperature.
Step 2: Recall the formula for Gibbs free energy change: , where R is the gas constant (8.314 J/mol·K), T is the temperature in Kelvin, and K is the equilibrium constant for the reaction.
Step 3: Convert the temperature from Celsius to Kelvin. Since the temperature is given as 25 °C, use the formula to find the temperature in Kelvin.
Step 4: Determine the equilibrium constant (K). The equilibrium constant can be derived from the energy difference between the axial and equatorial conformations. Typically, the equatorial conformation is more stable due to reduced steric hindrance, and the energy difference is often provided or can be looked up in reference materials.
Step 5: Substitute the values of R, T, and K into the formula to calculate the Gibbs free energy change. Ensure the units are consistent (e.g., R in J/mol·K, T in Kelvin, and K as a dimensionless quantity).
Risposta video verificata per un problema simile:
Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
1mConcetti chiave
Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.
Gibbs Free Energy (∆G°)
Gibbs Free Energy (∆G°) is a thermodynamic potential that measures the maximum reversible work obtainable from a thermodynamic system at constant temperature and pressure. It indicates the spontaneity of a reaction; a negative ∆G° suggests that the reaction is spontaneous, while a positive value indicates non-spontaneity. In the context of conformational changes, it helps predict the stability of different molecular conformations.
Video consigliato:
05:02
Breaking down the different terms of the Gibbs Free Energy equation.
Conformational Analysis
Conformational analysis is the study of the different spatial arrangements of atoms in a molecule that can be interconverted by rotation around single bonds. In cyclohexane derivatives, such as methylcyclohexane, the axial and equatorial positions significantly influence the molecule's stability due to steric interactions. Understanding these conformations is crucial for predicting the energy changes associated with their interconversion.
Video consigliato:
03:29Understanding what a conformer is.
Temperature and Reaction Conditions
Temperature plays a vital role in determining the Gibbs Free Energy and the equilibrium between different molecular conformations. At 25 °C, the standard conditions for thermodynamic calculations, the energy difference between axial and equatorial conformations can be quantitatively assessed. This temperature is often used as a reference point for calculating thermodynamic properties, making it essential for accurate predictions in organic chemistry.
Video consigliato:
Percorso guidato
3:22EAS Reactions of Pyridine Concept 3
Pratica correlata
Domanda del libro di testo
For each of the reactions in Problem 15, indicate which reactant is the nucleophile and which is the electrophile.
a.
b.
1615
views
Domanda del libro di testo
Why is the percentage of molecules with the substituent in an equatorial position greater for isopropylcyclohexane than for fluorocyclohexane?
1103
views
Domanda del libro di testo
The ∆G° for conversion of “axial” fluorocyclohexane to “equatorial” fluorocyclohexane at 25 °C is -0.25kcal/mol. Calculate the percentage of fluorocyclohexane molecules that have the fluoro substituent in an equatorial position at equilibrium.
1151
views
Domanda del libro di testo
Use curved arrows to show the movement of electrons in the following reaction steps
a.
b.
2806
views
Domanda del libro di testo
Identify the nucleophile and the electrophile in the following acid–base reactions:
a.
b.
3016
views