Jove
Visualize
Contáctanos
JoVE
x logofacebook logolinkedin logoyoutube logo
ACERCA DE JoVE
Visión GeneralLiderazgoBlogCentro de Ayuda JoVE
AUTORES
Proceso de PublicaciónConsejo EditorialAlcance y PolíticasRevisión por ParesPreguntas FrecuentesEnviar
BIBLIOTECARIOS
TestimoniosSuscripcionesAccesoRecursosConsejo Asesor de BibliotecasPreguntas Frecuentes
INVESTIGACIÓN
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchivo
EDUCACIÓN
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualCentro de Recursos para ProfesoresSitio de Profesores
Términos y Condiciones de Uso
Política de Privacidad
Políticas

Videos de Conceptos Relacionados

Arrhenius Plots02:34

Arrhenius Plots

48.8K
The Arrhenius equation relates the activation energy and the rate constant, k, for chemical reactions. In the Arrhenius equation, k = Ae−Ea/RT, R is the ideal gas constant, which has a value of 8.314 J/mol·K, T is the temperature on the kelvin scale, Ea is the activation energy in J/mole, e is the constant 2.7183, and A is a constant called the frequency factor, which is related to the frequency of collisions and the orientation of the reacting molecules.
The Arrhenius equation can be used...
48.8K
Temperature Dependence on Reaction Rate02:55

Temperature Dependence on Reaction Rate

90.5K
The Collision Theory
Atoms, molecules, or ions must collide before they can react with each other. Atoms must be close together to form chemical bonds. This premise is the basis for a theory that explains many observations regarding chemical kinetics, including factors affecting reaction rates.
The collision theory is based on the postulates that (i) the reaction rate is proportional to the rate of reactant collisions, (ii) the reacting species collide in an orientation allowing contact between...
90.5K
Introduction to Enzyme Kinetics01:19

Introduction to Enzyme Kinetics

35.7K
Enzyme kinetics studies the rates of biochemical reactions. Scientists monitor the reaction rates for a particular enzymatic reaction at various substrate concentrations. Additional trials with inhibitors or other molecules that affect the reaction rate may also be performed.
The experimenter can then plot the initial reaction rate or velocity (Vo) of a given trial against the substrate concentration ([S]) to obtain a graph of the reaction properties. For many enzymatic reactions involving a...
35.7K
Effect of Temperature Change on Reaction Rate02:28

Effect of Temperature Change on Reaction Rate

5.3K
The Arrhenius equation,
5.3K
The Integrated Rate Law: The Dependence of Concentration on Time02:39

The Integrated Rate Law: The Dependence of Concentration on Time

47.1K
While the differential rate law relates the rate and concentrations of reactants, a second form of rate law called the integrated rate law relates concentrations of reactants and time. Integrated rate laws can be used to determine the amount of reactant or product present after a period of time or to estimate the time required for a reaction to proceed to a certain extent. For example, an integrated rate law helps determine the length of time a radioactive material must be stored for its...
47.1K
E2 Reaction: Kinetics and Mechanism02:45

E2 Reaction: Kinetics and Mechanism

13.1K
SN2 substitutions and E2 eliminations of alkyl halides proceed via a concerted pathway. While the nucleophile attacks the alpha carbon in SN2 reactions, it functions as a strong base and abstracts a beta hydrogen in the E2 mechanism. The rate-limiting transition state in E2 elimination reactions is characterized by partially broken carbon–hydrogen and carbon–halogen bonds and a partially formed pi bond between the alpha and beta carbons. The beta hydrogen and halide are eliminated...
13.1K

También podría leer

Artículos Relacionados

Artículos vinculados a este trabajo por autores compartidos, revista y gráfico de citas.

Ordenar por
Same author

Rotational memory function of SPC/E water.

The Journal of chemical physics·2026
Same author

Dynamics of low-temperature water are driven by electrostatics.

The Journal of chemical physics·2026
Same author

Protein Electron Transfer in Solution, Protein Powders, and Electrode Confinement.

ACS omega·2026
Same author

Leveraging Multiproton-Coupled Electron Transfer to Improve Ir(III) Photocatalyst Efficiency.

The journal of physical chemistry. C, Nanomaterials and interfaces·2026
Same author

Photosynthetic Reaction Center: A Nonergodic, Dynamically Anisotropic, and Nonlinear Charge-Transport Engine.

The journal of physical chemistry letters·2025
Same author

Transient non-local interactions dominate the dynamics of measles virus N<sub>TAIL</sub>.

Communications chemistry·2025

Video Experimental Relacionado

Updated: Mar 18, 2026

Characterizing Electron Transport through Living Biofilms
08:52

Characterizing Electron Transport through Living Biofilms

Published on: June 1, 2018

9.0K

La cinética de transferencia de electrones en forma de campana de Marcus observada en un gráfico de Arrhenius

Morteza M Waskasi1, Gerdenis Kodis1, Ana L Moore1

  • 1School of Molecular Sciences and ‡Department of Physics, Arizona State University , Tempe, Arizona 85287, United States.

Journal of the American Chemical Society
|July 6, 2016
PubMed
Resumen

La teoría de Marcus de la transferencia de electrones predice una dependencia de velocidad en forma de campana. Los experimentos con una díada de fullereno-porfirina muestran que esta ley de velocidad es válida con los cambios de temperatura, no solo con las modificaciones químicas.

Más Videos Relacionados

Electrochemical Impedance Spectroscopy as a Tool for Electrochemical Rate Constant Estimation
08:41

Electrochemical Impedance Spectroscopy as a Tool for Electrochemical Rate Constant Estimation

Published on: October 10, 2018

26.0K
Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
09:33

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch

Published on: February 7, 2022

4.0K

Videos de Experimentos Relacionados

Last Updated: Mar 18, 2026

Characterizing Electron Transport through Living Biofilms
08:52

Characterizing Electron Transport through Living Biofilms

Published on: June 1, 2018

9.0K
Electrochemical Impedance Spectroscopy as a Tool for Electrochemical Rate Constant Estimation
08:41

Electrochemical Impedance Spectroscopy as a Tool for Electrochemical Rate Constant Estimation

Published on: October 10, 2018

26.0K
Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
09:33

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch

Published on: February 7, 2022

4.0K

Área de la Ciencia:

  • Química Física
  • La fotoquímica
  • Transferencia de electrones

Sus antecedentes:

  • La teoría de Marcus describe las tasas de transferencia de electrones basadas en la energía libre de reacción.
  • Una predicción clave es una dependencia de la tasa en forma de campana (parábola invertida).
  • Tradicionalmente, esto se observa mediante la alteración de las estructuras moleculares.

Objetivo del estudio:

  • Para verificar experimentalmente la predicción de la teoría de Marcus de una dependencia de tasa en forma de campana.
  • Investigar si la variación de temperatura, en lugar de la modificación química, puede inducir este fenómeno.
  • Para proporcionar una clara confirmación de la ley de la brecha de energía Marcus.

Principales métodos:

  • Estudió un sistema de diada de porfirina y fullereno.
  • Investigó la transferencia de electrones fotoinducida y la posterior recombinación de cargas.
  • Analizó la tasa de recombinación de carga como una función de la temperatura inversa.

Principales resultados:

  • Se observó una dependencia en forma de campana de la tasa de recombinación de carga en la temperatura inversa.
  • La tasa aumentó al enfriarse, luego disminuyó a temperaturas más bajas.
  • Este comportamiento no Arrhenius resultó de variaciones significativas de temperatura en la reorganización y las energías libres de reacción.

Conclusiones:

  • Demostró que la variación de temperatura puede inducir el efecto de la parábola invertida de Marcus.
  • Proporcionó una fuerte evidencia experimental para la ley de la brecha de energía de Marcus sin alteración química.
  • Destacó el papel de la reorganización dependiente de la temperatura y las energías libres de reacción en la cinética de transferencia de electrones.