Document Quality :: GCSE Chemistry Coursework Investigation

Document QualityMeasuring the rate of reaction, when dilute atomic number 11 thiosulphatesolution and dilute hydrochloric acid argon mixed.HypothesisI predict that the higher the concentration of sodium thiosulphate,the faster the rate of reaction.AimIn this experiment I intend to test the opposition theory. My aim is tosee if the concentration of sodium thiosulphate will affect the rateof reaction.IntroductionIn this experiment I will vary the concentration of sodiumthiosulphate to measure the rates of reaction. I will be mixingdifferent concentrations of sodium thiosulphate with hydrochloricacid, the collision theory says the reaction time will alter this iswhat I will be testing.The collision theory tells us that the larger the surface area, thefaster the reaction. So the higher the concentration the more than atomsthere are to react. on that point are 4 things that affect the rate ofreaction, concentration, surface area, catalysts and temperature.Concentration can affect th e rate of reaction by increasing atoms tocollide with each other. The more atoms there are to collide, thefaster the rate of reaction.In reactions where gases are involved, if you plus the squeezethe particles will move closer together. The smaller the space in thecontainer, collisions are more likely to occur. If the concentrationis weaker, this means there are fewer atoms to collide. If an objecthas a large surface area, the reaction rate will increase as there ismore surface area for the atoms to collide. I hypothesis that the moresurface area there is the more space there is for the particles toreact.Catalysts variegate the rate of chemical substance reactions but are not used up inthe reaction.Examples of catalysts are enzymes, clay, and hydrogen peroxide. Theseall speed up certain chemical reactions. Enzymes are tack together in thehuman body, they are there to break down food and make digestion timeshorter. Enzymes can also be found in washing powder, to break downfood sta ins on clothes. Temperature can affect the rate of reaction toa great extent because particles vibrate more at higher temperatures.The more they vibrate the more chance there is that they will collidewith another particle, thus causing the rate of reaction to increase.In a chemical reaction, the reactants collide with each other.PressureThis diagram shows us that the more pressure there is the more likelyit is that the particles will collide.High pressureLow pressureMore collisions as the particles are closer togetherNot many collisionsMarble in dilute hydrochloric acidThis diagram shows us that surface area does have an effect on therate of reaction.1 Large marble cube Marblecube split into 6 piecesIn the experiment I carry out, I will change the concentration and see