Rates of Reaction :: GCSE Chemistry Coursework Investigation

The affect of varying hydrochloric acid concentration of on the rate of reaction with sodium thiosulphateBackground knowledgeThe equation of this reaction is Na2S2O2+ 2HCl 2NaCl + body of water + SO2+ S A reaction is a process by which a substance orsubstances change to produce a new substance or substances. Rate ofreaction is the speed at which products are formed and reactantsdisappear during a chemical reaction. The rate will be measured by quest the production of sulphur. The rate of reaction is affectedby temperature, surface area, concentration and catalysts. These arethe affecting factors. In a reaction, the particles of the reagentmust come together and jar before the reaction can take place.This is called the collision theory, particles must collide beforethey can react, and the colliding particles must contain enough energyto cause bonds to brake. implement* Beaker* Log its unaccented meter* stand* black card* syringe* glass delivery tube* tripod* measuring cylinder* st op watchMethodWe unyielding to use a loggits sort out meter to follow the precipitationof sulphur on the basis that the hang passing finished the solutionwould decrease in intensity as the reaction proceeds. We will firstlycover the beaker with card, leaving a 2cm gap at the bottom of thebeaker to allow gently to pass through the solution. Secondly we wouldplace the loggits light meter directly above the beaker (the meterwill have the bottom half of it covered with the card to prevent any(prenominal)alien light from affecting the light intensity of the light passingthrough the water)PreliminaryAfter the first trial we had to change the way in which we covered thebeaker with the black card because we found that the amount of lightpassing through the solution from all angles was uncontrollable,because we were using a natural source of light (the sun). Instead ofleaving a 1cm gap from the bottom of the beaker, our solution was tocover the whole beaker and cut 2 arches, so that we could direct therequired amount of light into the specific area of the beaker.Secondly we will use a lamp, covered with 2 sheets of A4 paper toachieve a constant source of light. The Initial light intensityreading will be between 40% and 45%.ProcedureStep 1) Set up the stand to hold the log its light meter above thebeaker (fig i). Then place the beaker beneath the meter. Form ashielding from the surrounding light by using the black card, doing soby forming a cone around the beaker and the bottom half of the light