INCREASE THE CONCENTRATION OF REACTANTS
The more 'bunched together' the reactants the more often they will
collide.
The reaction of Magnesium with Hydrochloric acid is faster if the
concentration of the HCl is increased:
In everyday life, we know that charcoal in a barbecue burns much
faster when you fan it. This is because a higher concentration of
Oxygen in the air is then reacting with the charcoal.