Which one of the following factors does NOT affect the rate of a chemical reaction?

• A. The concentration of reactants
• B. The presence of a catalyst
• C. The temperature of the reaction mixture
• D. The color of the reactants

Answer: (D)

Verified step by step guidance

1. Understand that the rate of a chemical reaction depends on factors that influence how often and how effectively reactant molecules collide and react.
2. Recognize that the concentration of reactants affects the rate because higher concentration means more molecules per unit volume, leading to more frequent collisions.
3. Know that the presence of a catalyst affects the rate by providing an alternative reaction pathway with a lower activation energy, thus speeding up the reaction.
4. Acknowledge that temperature affects the rate because increasing temperature increases the kinetic energy of molecules, resulting in more frequent and energetic collisions.
5. Identify that the color of the reactants does NOT affect the rate of a chemical reaction, as color is a physical property related to light absorption and does not influence molecular collisions or reaction kinetics.