Question

Use the energy diagrams of the two reactions to answer the questions. Reaction A Reaction B 150 150 Energy 100 (kJ/mol) 100 Energy (kJ/mol) 50 50 0 0 Reaction progress Reaction progress What is the change in energy for reaction A? What is the change in energy for reaction B? AErxn = kJ/mol AErxn = kJ/mol What is the activation energy for reaction A? What is the activation energy for reaction B?

Answer 1

The change in energy for reaction A is 150 kJ/mol and for reaction B is -50 kJ/mol. The activation energy for reaction A is 50 kJ/mol and for reaction B is also 50 kJ/mol.

Step-by-step explanation:

The change in energy for reaction A can be calculated by subtracting the energy of the reactants from the energy of the products.

In this case, the change in energy for reaction A is 150 kJ/mol - 0 kJ/mol = 150 kJ/mol.

The change in energy for reaction B can be calculated the same way, which is 50 kJ/mol - 100 kJ/mol = -50 kJ/mol.

The activation energy for reaction A can be determined by subtracting the energy of the reactants from the energy at the peak of the reaction progress.

In this case, the activation energy for reaction A is 150 kJ/mol - 100 kJ/mol = 50 kJ/mol.

The activation energy for reaction B can be determined the same way, which is 50 kJ/mol - 0 kJ/mol = 50 kJ/mol.

Answer 2

Potential energy diagrams are used to illustrate the energy changes during a chemical reaction, from which one can determine the change in energy and activation energy for the reactions. Specific numerical answers require actual values from the diagrams.

Step-by-step explanation:

The energy changes during a chemical reaction can be visualized using potential energy diagrams, which show the difference in potential energy between reactants, transition states, and products throughout the reaction.

Change in Energy

For reaction A, the change in energy (∆Erxn) would be the difference in the energy level of the products minus the reactants. Similarly, for reaction B, the ∆Erxn is also calculated by subtracting the product's energy from the reactant's energy. If the potential energy of the products is higher than the reactants, the reaction is endothermic (∆Erxn > 0), and if it's lower, the reaction is exothermic (∆Erxn < 0).

Activation Energy

The activation energy (Ea) for a reaction is found by calculating the difference between the energy level of the transition state and the reactants. It represents the energy barrier that must be overcome for the reaction to proceed. Diagram A would depict a different Ea compared to Diagram B based on the energy of the transition state provided in each diagram.

Without specific values provided in the hypothetical diagrams, we cannot give numerical answers for ∆Erxn and Ea for reactions A and B. Normally, you would use the given energy levels on the diagram to calculate these values.