How the rate of reaction changes in a reaction between Hydrochloric Acid and Sodium Thiosulphate

Chemistry coursework:
An investigation of the affect of the concentration an of the rate of reaction.
Introduction.
We are trying to find out the affect of acid concentration on the rate of reaction, we are using 2, 1.5, 1, 0.5, 0.25 Molar acid. In our experiment, we are reacting it with sodium thiosulphate. The collision theory will be involved in this, for instance the more concentrated the acid we use, the faster the reaction will occur and the lower the concentration the slower the reaction will occur, this is because the collision theory says that if something is more concentrated th…