Video Transcript
Three compounds, a through c, are labeled in the reaction profile below. Which compound corresponds to the activated complex, otherwise known as the transition state?
In order for us to answer this question, we need to first identify how the reaction profile is related to a chemical reaction. In a chemical reaction, there are reactants on the left-hand side of the arrow. And when the chemical reaction occurs, products are formed which are on the right-hand side of the arrow. When relating a chemical reaction to the reaction profile, the same holds true. Reactants are on the left-hand side of the reaction profile, and products are on the right-hand side. When comparing the reactants to the products, we can see that the reaction is exothermic, since the energy of the products is lower compared to the energy of the reactants.
Now that we have identified reactants and products, let us recall the activated complex or transition state, which is a high-energy chemical structure, where chemical bonds in the reactants are being broken and new bonds are being formed. This activated complex only occurs for a very short period of time and is called the transition state because it occurs when the reactants are transitioning into the products.
When looking at the reaction profile, the area between the reactants and products is located here. Therefore, compound b corresponds to the activated complex, otherwise known as the transition state within the reaction profile.
