3. Consider the three step mechanism for a reaction is proposed for the synthesis of Formaldehyde: Step 1 Step 2 Step 3 H2 2H fast endothermic • co H• HCO нсо slow, endothermic H2CO fast, exothermic The reaction is overall exothermic. 1. What is the overall reaction? Draw a potential energy diagram for this reaction. Be sure to include ail necessary dentities such as E, AH, TS, reactants, products, etc.

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Energy (kJ/mol) Select the most appropriate reaction coordinate diagram for this reaction from the graphs shown below: Energy (kJ/mol) 10 a Ob C d 15 20 A Energy (kJ/mol) 25 B 20 15 10 0 0 Reaction Coordinate Reaction Coordinate 25 20 C 15 16 14 10 Energy (kJ/mol) D 12 10 0 Reaction Coordinate Reaction Coordinate The reason that this graph is the best choice is the highest rate constant goes with the second step and the reaction is exothermic the highest rate constant goes with the first step and the reaction is endothermic the highest rate constant goes with the first step and the reaction is exothermic the highest rate constant goes with the second step and the reaction is endothermic In order to speed up the reaction, the team should decrease the temperature of the soap solution increase the temperature of the soap solution keep the temperature of the soap solution the same because the reaction is endothermic the reaction is exothermic the hydrogen peroxide molecules will have…

Energy diagrams for two reactions are shown. Energy (kJ/mol) 1502 100- 50 Reaction progress Reaction A What is the heat of reaction for Reaction A? AH rxn A = What is the activation energy for Reaction A? kJ mol kJ Energy (kJ/mol) 150. 100- 50- Reaction progress Reaction B What is the heat of reaction for Reaction B? AHrxn B = What is the activation energy for Reaction B? Hint kJ mol kJ