Effect of Temperature on the Activation Energy

Effect of Temperature on the activating postcodeTitle Investigating the Effect of Temperature on the activation Energy be after A. HypothesisI predict that as temperature rises, the faster be the rank of fightion. The response that leave behind be studied in this experimentation is amid milligram and sulphuric stifling. This reception is shown in the chemical comparability at a press down placeMg (s) + H2S04 (aq) MgS04 (aq) + H2 (g)In this experiment, 0.4 grams of milligram ribbon ordain be used, together with deoxycytidine monophosphate cuboidal cen eonters of sulphuric acrimonious which is in excess. The variable that I volition be changing is the temperature of the body of water baths where the reactants (sulphuric acid and magnesium ribbon) will be fixed. The volume of the fluid (hydrogen gas) to be cleargond at separately varying water bath temperature is vitamin C cubic centimeters. The time it takes for to assemble 100 cubic centimeters of the hydrogen gas will be metric to calculate the rate of reaction.B. BackgroundThe fundamental basis of the collision speculation is the kinetic theory which describes the state of study in terms of the postcode of its particles, (Energex, two hundred6). According to Wilbraham and others (1997), the kinetic theory says that the tiny particles in all pee-pees of matter are in perpetual motion. When heated, the particles of the substance absorb vigour, some of which is stored inwardly the particles. This stored faculty does not raise the temperature of the substance. The rest of the goose egg goes into hurrying up the particles. Particles lacking the necessary kinetic energy to react still bump around but simply bounce back. Substances disperse to simpler forms, or form invigorated substances when supplied with sufficient energy, called the activation energy. The activation energy is a hindrance or an obstacle that the reactants must cross in order to decompose into simple r substances, or to combine and form new products.At higher temperatures, the particles of a substance move faster and become more energetic. Thus, increase temperatures serve up speed up the reaction by send-off increasing the add up of collisions of particles and cross e very(prenominal)where the energy barrier. Wilbraham and others argue that the main effect of increasing the temperature is to increase the number of particles that have enough kinetic energy to react when they collide. More colliding molecules are energetic enough to slip over the energy barrier to become products. The frequency of high energy collisions between reactants increase, thus, products form faster.The illustration above shows the basis for the postulate raising the temperature increases the rate of reaction because the added kinetic energy allows a larger fraction of reactants to go over the hill, (Norton, 2003).C. Risk AssessmentSulphuric acid is a strong, corrosive substance. Therefore, care shou ld be observed when performing the experiment. I will apply in mind the following inviolablety precautions to warrant a safe experimentTo protect the eyes from the strong acid, goggles should be worn. burster in handling the sulphuric acid should be observed. I will not pipette acid by mouth.The temperature of the water baths should be find out carefully to prevent scalding. The beaker with hot water bath should be correct up carefully to prevent it from being knocked over.D. Fair testTo ensure a fair test and high reliability of results from this experiment, I will observe the following measuresAll apparatus and equipment shall be cleareded after distributively time where the time it takes to collect 100 cc of hydrogen gas is obtained at distributively pull out of the experiment.The reading for the volume of the sulphuric acid shall be made very carefully by reading from the lower meniscus of the 100 cubic centimeter mark.The volume of the sulphuric acid and the weight do wn of the magnesium ribbon will be measured very accurately for all time measurements at every temperature level at each run of the experiment.The bung should be correctly and tightly placed to prevent the collected hydrogen gas from escaping.In order to acquire a constant and stable temperature for each time measurement, after adding the magnesium ribbon to the sulphuric acid, I will wait for 20 seconds to give way sure that the temperature is kept constant. . social function of the experimentMaterials askFor this experiment, the following are the materials that are to be used0.4 grams of magnesium ribbon100 cubic centimeters of 0.3 Molar sulphuric acid100 cc gas syringe for the collection of the hydrogen gas (H2)stopwatch for measuring the time it takes to collect 100 cubic centimeters of the H2 gasThermometer for measuring the temperature of the hot water baths200 cc conical flask for the sulphuric acid500 ml have cylinder for measuring the sulphuric acid500 ml beaker for th e water bathswater baths with the following temperatures 18.5C, 30C, 40C, 50C, 60C, and 70C.analytical balance for measuring 0.4 grams of magnesium ribbonProcedure1. Set up the materials while making sure that they are clean and the reagents are not contaminated.2. development a graduated cylinder, measure 100 cc of 0.3 molar concentration of sulphuric acid.3. Carefully weigh 0.4 grams of Magnesium ribbon using an analytical balance to make sure that the weight measurement is accurate.4. Pour the water bath with the desire temperature into the beaker.5. Carefully say the conical flask with the sulphuric acid and into the beaker with the water bath.6. Put the 0.4 grams of magnesium ribbon into the conical flask.7. Measure the time it takes to collect 100 cubic centimeters of hydrogen gas into the gas syringe.8. Repeat steps 1-7 for every desired temperature.10. Label the time recorded as run 1.11. Make 2 more runs for this experiment.IV. ResultsData Gathered The time measurements for each temperature of 18.5C, 30C, 40C, 50C, 60C, and 70C were obtained and tabulated under ( gameboard 1).Table 1. Temperature Measurements for the three hang ons or TrialsThe evaluate of reaction were obtained using the following formula down the stairs reply tramp = Volume of gas collected in cc / Time it takes to collect the gas in secondsThe calculated reaction rates (Volume / Time) for each set temperature for the three runs were tabulated beneathTable 2. Reaction judge of Each RunThe tabulated data of reaction rates above were therefore representical recordical recorded for all the three runs. The graph shows the same pattern for all the runs. chart 1 Reaction Rate Vs. Time graphical record of the Three RunsUsing the same data, the fair(a) of all calculated reaction rates for each set temperature in every run were taken and tabulated beneathTable 3 Average Reaction Rate for Each runThe average reaction rate of all the three runs are then graphed belowGraph 2 Aver age Reaction Rate Vs. Temperature.Determination of the Activation EnergyThe linear human relationship between a rate constant or reaction rate and temperature is given in the equation In k = -Ea/R X 1/T + In A, which is obtained from the Arrhenius equation that relates temperature, rate constant and activation energy. To solve this equation, the rate constant or reaction rate at several temperature determine obtained in the experiment are required. Activation energy can be calculated from the obtained temperature places and each respective rate constant by graphing In k versus 1/T. The In k values were obtained using a calculator, where for every value of reaction rate (k) entered into the calculator, the In function is pressed and the In k value was given. .Table 4 In K and 1 /T determine with the Corresponding Time and Rate of the First RunAfter obtaining the In k and 1 / T values for the first run, they were graphed as shown belowGraph 3 In k versus 1/T (First Run)The slope o f the In k versus 1/T graph for the first run was obtained the using a line of best sum through the points in the graph. A perpendicular line was drawn at points A and B. In the graph, A is mate to the distance between 0.6700 and 0.400 in the Y-axis and B is the distance between points 0.0033 and 0.0032 in the X-axis. So, to solve for the slope patronage A = 0.6740-0.400 = 0.2740 and for line B = 0.0033-.00032= -0.0001Slope = billet A / Line B = 0.02740 / 0.0001 = -2740Graph 4 In k Versus 1/T showing the SlopeThe relationship between slope and activation energy is slope = -Ea/R. Hence, the activation energy for the reaction for the first run is -2740= -Ea/R Ea = (-2740) (8.314J/mol) Ea= 22780.36 J/molSimilarly, data for the second run were obtained and tabulated as shown belowTable 4 In K and 1 /T Values with the Corresponding Time and Rate of the Second RunThe values of In k and 1/T for the second run were graphed as shown belowGraph 5 In k 1/T Graph for the Second RunThe slop e of the above In k versus 1/T graph for the second run was determined by drawing a perpendicular line in the best fit points much(prenominal) as in the graph of the first run. For the second run, the slope is equal to -1093.16So, the activation energy for the second run is -1093.16 = -Ea/R -Ea = (-1093.16) (8.314 J/mol) Ea = 9088.53 J/molData for the In k versus 1/T graph for the third run are as follows were similarly obtained and tabulated as followsThe graph of the tabulated data above is shown belowThe slope of the above In k versus 1/T above is -1274.70So the activation energy for the third run is -1267.89 = -Ea/R -Ea = (1267.89) (8.314 J/mol)Ea= 10541.23 J /molThus, the activation energy values for each run are the followingFirst run 22780.36 J/molSecond run 9088.53 J/mol deuce-ace run 10541.23 J /molV. AnalysisThe data gathered clear show that at higher temperatures, the rates of reactions increase up to a certain point, and then continue to slow down. This can be seen in the first 2 graphs, namely Graph 1 Reaction Rate Vs. Time Graph of the Three Runs and Graph 2 Average Reaction Rate Vs. Temperature. This means that after sometime, the rate of reaction slows down because the products are already being formed. In the experiment, the plateaus in the graph correspond to the time that the hydrogen gas (H2) are already being formed.The data likewise showed but one activation energy value for each run. Thus, it only shows that the activation energy in NOT temperature- dependent, NOR is there a estimate relationship between the two, since its value does not change with changes in temperature. The relationship between temperature and activation energy as can be reason in this experiment, is that the temperature increases the capacity of the system to subordinate the activation energy needed to form the products. So, the higher the temperature, the faster are the rates or speed of reactions.VI. EvaluationA. Experimental UncertaintyIn the measurement of the different temperatures for the water baths, the following per centum faultings were obtainedFor the reading of 18.5 C, the character error is summing up or damaging 0.5 / 18.5 x 100 = 2.7%For 30 C, the percentage error is Plus or minus 0.5 / 30 x 100 = 0.16%For 40 C, the percentage error is Plus or minus 0.5 / 40 x 100 = 0. 125%For 53 C, the percentage error is Plus or minus 0.5 / 53 x 100 = 0. 94%For 60 C, the percentage error is Plus or minus 0.5 / 60 x 100 = 0. 83%For 70 C, the percentage error is Plus or minus 0.5 / 60 x 100 = 0. 71%In the use of a graduated cylinder with 1 cm scale, the percentage error is plus or minus 0.5 in every 10 cm scale. So, in this experiment, the percentage error can be calculated as0.50/100 X 100 = 0.5%.Experimental OutcomesThe impressions of the experiment exactly fit my hypothesis or prediction, that as the temperature rises, the faster is the rate of reaction.However, I did not predict the outcome that the activation energy itself is NOT temperature dependent, since it does not change with the changes in temperature. This is shown in the experiment results, where there was only one activation energy value for all temperature measurements in each run of the experiment. The relationship between temperature and activation energy is based on the fact that the temperature increases the capacity of the system to overcome the activation energy needed to form the products.Design of the ExperimentI believe that to improve the experiment, I may need to compare the reaction used inthis experiment to a reaction that uses a gas pedal to investigate the effect of catalysts on the activation energy and speed of reactions.ReferencesActivation Energy, 2006. http//chemed.chem.purdue.edu/genchem/topicreview/bp/ch22/activate.htmlactAccessed February 28, 2006.Collins, M. (1999), Activation Energy and the Arrhenius Equation. Abbey Newsletter, Vol.23, Number 3, 1999. http//palimpsest.stanford.edu/byorg/abbey/an/an23/an23-3/an23-308. html. Accessed February 29, 2006.Energex, 2006. Kinetic Theory. http//www.energex.com/au/switched_on/project_info/electricity_production_glossary.htmlK. Accessed February 29, 2006.Norton, 2003. signalise Equations and Concepts .Chemistry in the Science Context. http//www.wwnorton.com/chemistry/concepts/chapter14/ch14_5.htm Accessed February 27, 2006.The Shodon Education Foundation, Inc. 1998. The Arrhenius Equation. http//www.shodor.org/UnChem/advanced/kin/arrhenius.html. Accessed February 27, 2006.Wikipedia, 2006. contact Theory. http//en.wikipedia.org/wiki/collision_theory. Accessed February 27, 2006.Wilbraham, A. Stanley D., Matta, M., 1997. Chemistry. 4th edition. Menlo Park, California Addison-Wesley. (pp.490-494)..