4.18 explain the effects of changes in surface area of a solid, concentration of solutions, pressure of gases and temperature on the rate of a reaction in terms of particle collision theory

4.18 •more collisions increase the rate of reaction 

                  •surface area: •by breaking up a solid, it increases it’s surface area

                                                   •this means particles around it in the solution will have more area to work on, so there’ll be useful collisions more often 

                  •concentration: •if it’s more concentrated, there are more particles, increasing the

                                             probability of collisions 

                                           •increasing the pressure in the gas does the same thing

                                                    •as the reaction passes, there are fewer reactant particles, so they collide less frequently, so the rate slows down

                  •temperature: •when the temperature is increased, the particles have more energy and move faster so the collide more frequently and successfully 

                                                   •faster collisions are only caused by increasing the temperature 

                  •catalyst: •a solid catalyst works by giving the reacting particles a surface to stick to 

                                           •they increase the number of successful collisions by lowering the activation energy