Transition state

Definition

The transition state is a high-energy, unstable configuration of atoms during a chemical reaction that represents the point of maximum energy. It is the state through which reactants must pass to be converted into products.

5 Must Know Facts For Your Next Test

1. The transition state corresponds to the highest point on the reaction coordinate diagram.
2. It is not a stable species that can be isolated; it exists momentarily.
3. The activation energy of a reaction is the energy difference between the reactants and the transition state.
4. Transition states are critical in determining the rate of a chemical reaction according to collision theory.
5. $\Delta G^{\ddagger}$ (Gibbs free energy of activation) quantifies the energy barrier that needs to be overcome to reach the transition state.

Review Questions

Related terms

Activation Energy:

The minimum amount of energy required for reactants to form products, corresponding to the energy needed to reach the transition state.

Reaction Coordinate:

A graph showing changes in potential energy as reactants are converted into products, with peaks representing transition states.

$\Delta G^{\ddagger}$: \( \Delta G^{\ddagger} \) (Gibbs free energy of activation) denotes the free energy difference between reactants and their transition state.