Answer:
solution concentration
Step-by-step explanation:
Among the options given in the above question, solution concentration will affect the rate of a chemical reaction. This is because an increase in reagent concentration speeds up the reaction because there will be a greater number of reagent particles per unit volume, increasing the likelihood of effective collisions between them.
In addition to concentration, the factors that can influence the rate of a chemical reaction are temperature, catalyst, pressure and contact surface.