The Effect of Temperature on Rate of Reaction Essay Example for Free

The Effect of Temperature on Rate of Reaction EssayIn this sample I shall be investigating how temperature affects the reckon of reactionRates of reactionThe Factors that affect the rate of reaction are temperature, surface sphere of influence, concentration, gas pedals, light and pres receivedSurface firmament Surface area is the amount of solid surface that is available for reaction Only affects solids so this depart not affect our experiment When the surface area increases the rate of reaction increases as there is much surface area for the particles to work on, thus, there are more collisions per second Example It is easier to light a fire with small pieces of stick than using large blocks of woodConcentration Concentration is the amount of molecules of a substance in a given wad Concentration affects solids, gases and runny so this entrust affect our experiment When the concentration increases the rate of reaction increases as there are more molecules present, t herefore there are more collisions between molecules (Collision theory) Example zinc reacts fairly slowly with dilute hydrochloric stifling however when the acid is concentrated, the rate of reaction increases. Catalysts A catalyst is a substance which speeds up therate of reaction without itself going undergoing any permanent chemical change this means only small amounts of catalysts are needful to speed up reactions When a catalyst is involved in an experiment there is slight competency needed for the reaction therefore there is more collisions per second We will not be using catalysts in our experiment Example Decomposing henry peroxide resolving power at room temperature is very slow, but using a small amount of manganese oxide greatly increases the reaction rate and oxygen is given off rapidlyLight Light is a form of energy and it causes many chemical reactions to view place. Light does not affect our experiment Example PhotosynthesisTemperatureCollision theor y is used to explain how opposite factors affect the rate of a chemical reaction. For a reaction to take place the reactant particles must collide with each other with adequate energy (activation energy), this energy is used to break the bonds between the particles. If the particles do not have enough energy they will bounce off each other without reacting. By increase the temperature the particles gain more energy and move faster causing more collisions per second.10oC 60oCPrevious ExperimentsThese previous experiments give us background information on judge of reactionAcid and limestoneCaCO3(s) + 2HCL(aq) CaCl2(aq) + H2O(l) + CO2(g)Apparatus Conical flask, hydrochloric acid, marble chips, cotton wool and scalesIn this experiment we melt a certain mass of large marble chips with a certain volume of hydrochloric acid in a conical flask and use cotton wool to trap the acid spray. As the atomic number 6 dioxide is given off from the flask, the mixture loses mass, this is measured and recorded every minute until the reaction is over. The experiment is repeated again using the same mass of marble chips and the same volume of hydrochloric acid and the same temperature but instead using small marble chips. When we meet at our results we scrape up that the larger marble chips take more time to react than the smaller marble chips which show that as the surface area increases, the rate of reaction increases.Decomposition of hydrogen peroxide solutionH2O2(aq) 2H2O(l) + O2(g)Apparatus Conical flask, gas syringe, hydrogen peroxide solution and solid manganese oxideIn this experiment we firstly measure the time taken for hydrogen peroxide to decompose and produce 50cm3 of oxygen at room temperature and without a catalyst. We use a gas syringe to measure the oxygen given off. thence we repeat the experiment but instead add a small amount of solid manganese oxide to the hydrogen peroxide solution. When we look at our results we find that without the catalyst (mangane se oxide) the reaction is very slow, but when we add the catalyst the decomposition is very fast and oxygen israpidly given off which shows that catalysts increase the rate of reaction.Sodium thiosulphate and hydrochloric acidNa2S2O3(aq) + 2HCL(aq) 2NaCl(aq) + SO2(g) + S(s) + H2O(l)Apparatus Sodium thiosulphate, hydrochloric acid, stop clock, a measuring cylinder and white paper with a black crossIn this experiment we vary the concentration of the sodium thiosulphate, add it to a given volume of hydrochloric acid and time how long it takes for the mixture to go cloudy and the cross to disappear. When we look at our results we see that as we increase the concentration of sodium thiosulphate the rate of reaction increases.HypothesisMy prediction is, as the temperature of the reaction mixture increases so to will the rate of reaction as at higher temperatures the particles have more energy and will collide more hence increasing the rate of reaction. This is explained by the collision theory. The collision theory also allows me to predict that my time against temperature graph will have negative correlation as the time taken will decrease as the temperature increases. I also predict this graph will be curved as the time taken will not be directly proportional to the temperature. I also predict that as I increase the temperature of the mixture, the time taken for the cross to disappear will decrease.ReactionIn my experiment I shall be investigating the effect of temperature on a reaction rate by reacting sodium thiosulphate in dilute hydrochloric acid as shown in the equation down the stairsSodium + hydrochloric Sodium + Sulphur + Sulphur + Water thiosulphate acid chloride dioxideNa2S2O3 (aq) + 2HCL (aq) 2NaCl (aq)+ SO2 (g) + S (s) + H2O (l) Sodium thiosulphate is a clear liquid and hydrochloric acid is a clear liquid, when they react together the solution turns cloudy due to the sulphur.The reaction is exothermic as the energy required to break the bonds is les s than the energy needed to make new bonds.ProcedureApparatus Conical flask Measuring cylinder Bunsen burner Thermometer Stop clock White paper with a black crossMethod1. Measure out 10 cm3 of sodium thiosulphate and 40cm3 of water into a flask. Measure out 5 cm3 of hydrochloric acid an a measuring cylinder 2. Heat the thiosulphate solution to the required temperature using a Bunsen burner 3. Add the acid and start the stop clock. Swirl the flask to mix the solutions and put the solution on the white paper with a black cross 4. Look down at the cross and stop the clock and feel the time taken when the cross has disappeared. Record the temperature of the mixture in the flask.VariablesThe versatiles we will need to keep constant are The concentration of sodium thiosulphate The concentration of hydrochloric acid The volume of hydrochloric acid The same colour of cross The same thickness of cross Look at the cross from the same heightThe independent variable is the temperature. We wil l take 7 different recordings between 10o-70o We will do each recording 5 times and get an average to make sure the results are accurate.ResultsI will record my results in the table and make a time against temperature and a 1/time against temperature graph as shown below