1. The problem statement, all variables and given/known data Classify the following actions based on how they could affect a reaction rate (rate increases, rate decreases, rate is unaffected) and provide a brief explanation as to why: Add a catalyst Decrease the concentration of a reactant Decrease the surface area of a solid reactant Increase the temperature 2. Relevant equations N/A 3. The attempt at a solution Add a catalyst - Rate increases; change reaction mechanism to include steps with lower activation energies. Decrease the concentration of a reactant - Rate decreases; decreases the chance for collisions since there are less reactant molecules in a given area. Decrease the surface area of a solid reactant - Rate decreases; less collisions because less particles exposed to the other reactant. Increase the temperature - Rate increases; increase in the kinetic energy of the molecules and causing them to move faster and collide more often. Thus, more molecules can achieve the required activation energy. Can anyone confirm if I am on the right track? I am especially unsure about the decrease in the surface area of a solid reactant. Is the phase significant in this case? Thanks. All help Is very much appreciated.