What term describes the minimum energy that must be overcome for a chemical reaction to occur?

What term describes the minimum energy that must be overcome for a chemical reaction to occur?

• A. Catalyst
• B. Activation Energy
• C. Activated Complex
• D. Spontaneous

Answer: (B)

Activation energy is the minimum energy required for reactants to reach the transition state and form products. On a potential energy diagram, reactants sit at a certain energy level and must climb to the peak—the activated complex—before any transformation occurs. The difference in energy between the reactants and that peak is the activation energy. This barrier largely controls how fast a reaction proceeds: a smaller barrier means more molecules have enough kinetic energy to cross, speeding up the reaction; a larger barrier slows it down. Temperature shifts the distribution of molecular energies, so heating helps more molecules overcome the barrier. Catalysts lower this barrier by providing an alternative pathway, increasing the rate without changing the overall energy change of the reaction. The activated complex is the high-energy, short-lived arrangement at the top of the barrier, not the energy you must supply itself. Spontaneous describes whether a reaction can occur without external energy input, which is not about the energy barrier.

Activation energy is the minimum energy required for reactants to reach the transition state and form products. On a potential energy diagram, reactants sit at a certain energy level and must climb to the peak—the activated complex—before any transformation occurs. The difference in energy between the reactants and that peak is the activation energy. This barrier largely controls how fast a reaction proceeds: a smaller barrier means more molecules have enough kinetic energy to cross, speeding up the reaction; a larger barrier slows it down. Temperature shifts the distribution of molecular energies, so heating helps more molecules overcome the barrier. Catalysts lower this barrier by providing an alternative pathway, increasing the rate without changing the overall energy change of the reaction. The activated complex is the high-energy, short-lived arrangement at the top of the barrier, not the energy you must supply itself. Spontaneous describes whether a reaction can occur without external energy input, which is not about the energy barrier.