What ways do enzymatic catalysts increase the rates of reactions?
They shift the reaction equilibrium toward the products.
They increase the concentration of reactants.
They decrease the free energy of the reaction.
They promote the formation of a transition state.
They lower the activation energy of the reaction.
The correct answer and explanation is:
The correct answer is: They lower the activation energy of the reaction.
Enzymatic catalysts increase the rate of chemical reactions by lowering the activation energy required for the reaction to proceed. Activation energy is the energy barrier that must be overcome for reactants to be converted into products. Enzymes achieve this by providing an alternative reaction pathway with a lower activation energy. This allows the reaction to proceed faster, even at lower temperatures.
Enzymes do not alter the equilibrium of a reaction, meaning they do not change the relative concentrations of reactants and products at equilibrium. They only accelerate the rate at which equilibrium is reached. They also do not increase the concentration of reactants, as this is determined by external factors such as concentration changes or reaction conditions, not by the enzyme itself.
Enzymes do not change the free energy (ΔG) of the reaction. The free energy difference between reactants and products remains the same, meaning enzymes do not affect the thermodynamic properties of the reaction. Instead, they only impact the kinetic aspect by lowering the activation energy.
Enzymes help promote the formation of the transition state by binding to the reactants and stabilizing this high-energy, unstable intermediate. This stabilization reduces the energy required for the transition state to form, making the reaction more likely to occur.
In summary, enzymes speed up reactions by lowering the activation energy, which enables the reaction to occur more quickly without affecting the equilibrium or the free energy change of the reaction.