Question

which statement best describes how a catalyst can speed up a chemical reaction?
the catalyst decreases the activation energy needed
the catalyst increases the concentration of products
the catalyst binds to enzymes to release substrates
the catalyst increases the concentration of reactants

Explanation:

To determine how a catalyst speeds up a chemical reaction, we analyze each option:

• A catalyst does not increase activation energy (that would slow reactions), so the option "The catalyst increases the activation energy needed" is incorrect.
• Catalysts don't directly increase product concentration; they speed up the rate to reach equilibrium faster, so "The catalyst increases the concentration of products" is wrong.
• Catalysts (in general, not just related to enzymes in this context) don't function by binding to enzymes to release substrates as a primary mechanism for speeding up all reactions, so "The catalyst binds to enzymes to release substrates" is incorrect.
• A catalyst works by lowering (decreasing) the activation energy required for the reaction to occur, which allows more reactant molecules to have enough energy to react, thus speeding up the reaction. So the correct statement is "The catalyst decreases the activation energy needed".

Answer:

The catalyst decreases the activation energy needed