The Effect of Concentration on the Rate of Reaction :: GCSE Chemistry Coursework Investigation

The effect of constriction on the rate of reply in the midst of sodium thiosulphate and dilute hydrochloric acerbicThis investigation is about rates of reply and what affects them.In this case I am going to look at hydrochloric acid and sodiumthiosulphate which is a precipitation reaction causing the resolution togo cloudy. They react as in the equations belowsodium thiosulphate + hydrochloric acid - sodium chloride + sulphur +sulphur dioxide + waterNa2S2O3(aq) + 2HCl(aq) - 2NaCl(aq) + S(s) + SO2(g) + H2O(l)A reaction volition only slip by where the particles of the reactants meetand combine. This is called the collision theory. For a reaction tooccur particles have to conflict with each other. further a small per centumresult in a reaction. This is due to the energy barrier to traverse.Only particles with enough energy to overcome the barrier leave react by and by colliding. The minimum energy that a particle must have toovercome the barrier is called the activation ene rgy, or Ea. The sizeof this activation energy is distinguishable for different reactions. If thefrequency of collisions is annexd the rate of reaction will amplification. nonetheless the percent of successful collisions remains thesame. An increase in the rate of reaction can be achieved byincreasing the frequency of collisions. Therefore to increase the rateof reaction it is necessary to cause more particles to collide harderand collide more often. There are several ways to do this and these line up the factors for this experiment. They are listed below alongwith predictions as to their affect on the reaction.Possible FactorsTo make sure I carry out a fair test I will only change theconcentration of sodium thiosulphate. I will keep the followingfactors the same.Increasing the hale. By reducing the volume in which the sameamount of particles exist the pressure is increased. Once the samenumber of particles are in a littler area there is less space in whichto move and so the part icles are more likely to hit each other. It is and so workable to predict that increasing the pressure will resultin an increase in the rate of reaction. I will not test this versatilebecause we dont have the facilities to test it. However pressure is acontinuous variable.Catalyst. A catalyst is a separate substance that speeds up areaction. subsequently the reaction has happened it gets left behind. Thismakes this variable unsuitable for the type of experiment I am goingto do.Temperature. By giving the particles extra energy they will movefaster. This means that they cover more ground and are therefore more