Question

2C) [8 pts) For some chemical reactions reactants are favored at high temperature despite the reactants having a higher energy ground state. Qualitatively Illustrate such a reaction. Your sketch should include energy levels and energy level occupancies

Answer 1

Answer: chemical reaction occurs when reactants change to products crossing an energy barrier called activation energy. even if the reactants are at higher energy ground state it need much more energy to become an activated complex or to reach excited state from which the products are formed. inorder to form this transition state the reactants are supplied with energy. transition states are higher energy level states or excited states. more over in the chemical reactions some bonds are broken and new bonds are formed but it involves the transition states. this is the reason why some reactions are favored at higher temperature. you can find many examples for this kinds of reactions. all coupling reactions especially palladium catalysed zuzuki coupling or aromatic halides or sonagachira coupling reaction etc. the following figure is a an energy level diagram of catalysed and non catalysed path way where CO2 is added to some organic compounds of high energy.

High-energy starting material e.g. Energy Hydrogen Alkenes [kJ/mol] Non catalyzed reaction Alkynes Ерохides Amines Low-energy product e.g. Carboxylic acids- Esters 0 Catalyzed reaction Lactones Carbonates Carbamates со, -393