True statement for Catalyst ___________
I. make a spontaneous reaction is not spontaneous
II. accelerate the reaction forward and slow reverse reaction
III. lowering the activation energy of the forward reaction
IV. lowering the activation energy of the reverse reaction
The correct statement that describes the role of a catalyst is:
III. lowering the activation energy of the forward reaction
To understand why this is the correct statement, let's first define what a catalyst is. A catalyst is a substance that increases the rate of a chemical reaction by providing an alternative reaction pathway with a lower activation energy. The activation energy is the energy required for a reaction to occur.
Now, let's analyze the other statements:
I. "make a spontaneous reaction not spontaneous": This statement is incorrect. A catalyst has no influence on the spontaneity of a reaction. It only affects the rate of reaction.
II. "accelerate the reaction forward and slow the reverse reaction": This statement is partially correct. A catalyst can indeed speed up the forward reaction by lowering the activation energy, but it does not necessarily slow down the reverse reaction. The effect of a catalyst on the reverse reaction can vary depending on the specific reaction and conditions.
IV. "lowering the activation energy of the reverse reaction": This statement is incorrect. A catalyst does not directly lower the activation energy of the reverse reaction. It primarily affects the forward reaction by providing an alternative pathway that requires less energy.
In conclusion, statement III, "lowering the activation energy of the forward reaction," is the true and most accurate statement regarding the role of a catalyst.