Draw an energy versus reaction progress diagram (similar to...

Draw an energy versus reaction progress diagram (similar to the one in Question 60 ) for each of the reactions whose activation energy and enthalpy change are given below. Draw arrows to represent the activation energies of the forward and reverse reaction and $\Delta_{1} H^{\circ} .$ (a) $\Delta_{r} H^{\circ}=-145 \mathrm{~kJ} \mathrm{~mol}^{-1} ; E_{\mathrm{a}}=75 \mathrm{~kJ} \mathrm{~mol}^{-1}$ (b) $\Delta_{r} H^{\circ}=-70 \mathrm{~kJ} \mathrm{~mol}^{-1} ; E_{\mathrm{a}}=65 \mathrm{~kJ} \mathrm{~mol}^{-1}$ (c) $\Delta_{r} H^{\circ}=70 \mathrm{~kJ} \mathrm{~mol}^{-1} ; E_{\mathrm{a}}=85 \mathrm{~kJ} \mathrm{~mol}^{-1}$

Draw an energy versus reaction progress diagram (similar to the one in Question 60 ) for each of the reactions whose activation energy and enthalpy change are given below. Draw arrows to represent the activation energies of the forward and reverse reaction and $\Delta_{1} H^{\circ} .$
(a) $\Delta_{r} H^{\circ}=-145 \mathrm{~kJ} \mathrm{~mol}^{-1} ; E_{\mathrm{a}}=75 \mathrm{~kJ} \mathrm{~mol}^{-1}$
(b) $\Delta_{r} H^{\circ}=-70 \mathrm{~kJ} \mathrm{~mol}^{-1} ; E_{\mathrm{a}}=65 \mathrm{~kJ} \mathrm{~mol}^{-1}$
(c) $\Delta_{r} H^{\circ}=70 \mathrm{~kJ} \mathrm{~mol}^{-1} ; E_{\mathrm{a}}=85 \mathrm{~kJ} \mathrm{~mol}^{-1}$

Key Concepts

Arrow Representation in Diagrams

Arrows in an energy versus reaction progress diagram are used to illustrate the magnitude of the activation energies for both the forward and reverse reactions, as well as the overall reaction enthalpy change. These arrows provide a visual means of comparing the energy barriers and making clear the endothermic or exothermic nature of the reaction.

Reaction Enthalpy (?H)

Reaction enthalpy is the net change in energy between the reactants and products. It signifies whether a reaction is exothermic (releasing energy) or endothermic (absorbing energy), and it is depicted on a reaction coordinate diagram as the vertical difference in energy levels between the starting materials and the final products.

Forward and Reverse Activation Energies

In a reaction coordinate diagram, both the forward and reverse reactions have unique activation energy barriers. The forward activation energy is the energy required to go from reactants to the transition state, while the reverse activation energy is the energy needed to go from products back to the transition state. These values help in understanding the kinetic feasibility and the relative speeds of the forward and reverse processes.

Reaction Energy Diagram

A reaction energy diagram, or reaction coordinate diagram, graphically represents the change in potential energy of a system as the reaction progresses from reactants to products. This diagram helps visualize the energy barrier (activation energy) that must be overcome and the overall energy change (reaction enthalpy) associated with the chemical process.

Activation Energy

Activation energy is the minimum energy that reactant molecules must possess to reach the transition state and form products. It is graphically represented as the energy difference between the reactants (or products in the reverse reaction) and the highest point on the reaction coordinate diagram, indicating the energy barrier that must be overcome during the reaction.

Transcript

Please give Ace some feedback