-Increase the concentration (pressure in gases). (1) This increases the likelihood and frequency of collision because the particles of reactant will be closer together (1)-Increase the temperature(1). This increases the kinetic energy of the particles,both increasing the frequency of collisions and increasing the likelihood that they will have enough energy to react (1)-Increasing the surface area (if the reactant is solid) (1). This increases the number of particles of the solid reactant that is able to come together with other reactants, therefore increasing the frequency of collisions (1)-Using a catalyst(1). This is a substance that speeds up the rate of the reaction by lowering the activation energy needed for the reaction to take place (1)