Which of the following scenarios would increase the reaction rate of a chemical reaction the most?

• A. Decreasing the concentration of reactants by half
• B. Increasing the temperature by 20 °C
• C. Adding an inert gas at constant volume
• D. Lowering the pressure for a reaction involving only solids

Answer: (B)

Verified step by step guidance

1. Understand that the reaction rate depends on factors such as concentration, temperature, pressure, and the presence of catalysts or inert gases.
2. Recall that increasing temperature generally increases reaction rate because it raises the kinetic energy of molecules, leading to more frequent and energetic collisions.
3. Consider the effect of decreasing reactant concentration by half, which typically decreases the reaction rate since fewer reactant molecules are available to collide.
4. Analyze the impact of adding an inert gas at constant volume: since the volume and concentration of reactants do not change, the reaction rate remains largely unaffected.
5. Recognize that lowering pressure for reactions involving only solids usually has little to no effect on reaction rate because solids are incompressible and their concentration does not change significantly.