Just as increasing the pressure will increase the number of particles colliding, so will the concentration. By putting more particles into the reaction, the chance of them colliding increases and so the rate increases. This variable is continuous and independent. I shall test this variable. I predict that by doubling the concentration of the acid, the rate of reaction will double.
Particles can only collide when the two sorts can meet.
Therefore a reaction can only occur on the surface of the material. Therefore by increasing the area of the material which is available to collide the speed of the reaction will increase. I predict that doubling the surface area will double the speed of the reaction. This variable is continuous but I shall not test it because it is hard to control the exact surface area of the two reactants as they both come in an aqueous solution. I am going to test the two variables concentration and temperature .