The potential energy of the activated complex is equal to the sum of

An activated complex is an intermediate state that is formed during the conversion of reactants into products. An activated complex is the structure that results in the maximum energy point along the reaction path. The activation energy of a chemical reaction is the difference between the energy of the activated complex and the energy of the reactants.

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How an Activated Complex Works
Activated Complex Versus Transition State
What is the potential energy of the activated complex?
What is the activation energy of a reaction equal to?
How does the potential energy of the activated complex compare?
What is an activated energy and activation complex?

How an Activated Complex Works

Consider a chemical reaction between reactants A and B to form products C and D. The reactants must collide with each other and interact in order to form the products. Several factors improve the chances that A and B will encounter each other, including increased temperature, increased concentration of reactants, or adding a catalyst. In a reaction with an activated complex, A and B form the complex A-B. The complex only forms if sufficient energy (the activation energy) is present. The energy of the activated complex is higher than that of either the reactants or products, which makes the activated complex unstable and temporary. If there isn't enough energy for the activated complex to form the products, it eventually breaks apart into the reactants. If enough energy is available, the products form.

Activated Complex Versus Transition State

Some textbooks use the terms transition state and activated complex interchangeably, but they mean different things. The transition state refers only to the highest potential energy of the atoms participating in a chemical reaction. The activated complex covers a range of atom configurations that atoms form on their way from reactant to products. In other words, the transition state is the one molecular configuration that occurs at the peak of the energy diagram of the reaction. The activated complex may be present at any point near the transition state.

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Helmenstine, Anne Marie, Ph.D. "What Is an Activated Complex?" ThoughtCo. https://www.thoughtco.com/definition-of-activated-complex-605819 (accessed December 29, 2022).

We can show energy changes during a chemical reaction using energy profiles. The energy profile of the reaction between nitrogen dioxide and carbon monoxide is shown on the left while the equation is given below.

NO2(g) + CO(g) => CO2(g) + NO(g) ΔH= –226 kJ mol–1

The symbol ΔH is the difference between H(products) - H (reactants)The negative sign indicates that energy is given out.

As you can see from the energy profile, the chemical energy of the reactants is greater than the products. The difference in energy is given out, during the reaction, as heat.

Initially, when mixed together, the reactants lack sufficient energy to react. Their collisions are not strong enough to initiate a reaction by breaking bonds.

After a small amount of energy is supplied, known as activation energy, the reaction proceeds. In this case the activation energy for this reaction is shown on the energy profile as 132 kJ mol–1. An activated complex forms which then splits to form the products.

the difference of the potential energy of the reactants and products is equal to the energy of the activated complex the total potential energy of the reactants is higher than the total potential energy of the products the sum of the potential energies of the reactants and products is equal to the energy of the activated complexthe total potential energy of the reactants is lower than the total energy of the products.

Solution : The following is the potential energy profile for an exothermic reaction:
The plot shows th echange in potential energy as reactants `A` and `B` are convertited to products `C` and `D` . The activated complex is a highly unstable species with a high potential energy. The activation energy of the backward reaction, `(E_(a))_(b)` , is greater than the products `(C and D)` are more stable than the reactants `(A and B)` .
Energy of activation of an exothermic reaction or an endothermic reaction is always positive.

What is the potential energy of the activated complex?

The potential energy difference between the reactant and the activated complex is called activation energy. The minimum amount of energy needed for the particles to react is called the threshold energy.

What is the activation energy of a reaction equal to?

The activation energies are defined as the energy of the transition state for a given reaction relative to the initial state:Ea=ΔETS−ΔEIS.

How does the potential energy of the activated complex compare?

How does the energy of the activated complex compare with the energies of reactants and products? It is higher than the energy of both reactants and products.

What is an activated energy and activation complex?

An Activated Complex is a high energy state that a reaction goes through in order to change reactants to products. You can see here in the picture just how high energy the complex is. Activation Energy is what is required to overcome this complex. With the complex overcome, reactants become products.