The effect of reactant concentration Essay Example for Free

The effect of reactant concentration demonstrateThen pour the totality of atomic number 11 Thiosulfate using a step cylinder to the cone-shaped flask, the quantity will vary depending on the sample. 4. Rinse the measuring cylinder in water under the hip-hop to clean it of excess sodium thiosulfate. 5. Pour the water from the measuring cylinder into the conic flask (already containing the Sodium Thiosulfate), the amount of water will vary depending on the sample. 6. Draw a cross on a blank piece of paper. 7. Place the conelike flash containing the water and Sodium Thiosulfate mixture directly on top of the cross on the paper. 8. Collect 5 ml of Hydrochloric Acid using the clean measuring cylinder. 9. Keep the stop watch ready to time the reply time once the Hydrochloric Acid is added to the cone-shaped flask. 10. Transfer all of the 5 mL of Hydrochloric Acid into the conical flask and swirl the conical flask to start the answer and begin timing. 11. Stop timing and r ecord the time taken, when you faeces no all-night see the cross drawn on the paper. 12. Repeat steps 2-11 for each sample while ever-changing the some of the variants. Variables Independent VariableThe variable that changes in the investigation is the amount of Sodium Thiosulfate in the solution. certified Variable For this experiment the measured variable is the time taken for the reaction to conclude. This was measured in seconds. Controlled Variables o The amount of water in solution this was added to ensure that 50 mL of mixture was contained within the flask for each sample case. o Temperature o Amount of Hydrochloric acid 5 mL each time. Results We spy that when the HCL was added into the conical flask that a murky perception formed in the solution thus the prepare solution turned unclear.This can be explained by the following chemical reaction taking turn out 2HCL (aq) + Na2S2O (aq) S(s) + SO2 (g) + H2O The table below captures the results we obtained Table 1 Sample 2M HCL Amount of Na2S2O Amount of H2O compactness of Na2S2O Time mL mL mL M Sec Graph 1 Graph 2 Discussion By collecting the results from the investigation we were able to come to a conclusion on the affects of change the amount of Na2S2O and water has on the reaction of a solution.Graph 1 and Table 1 supra shows the amount of Na2S2O and the amount of water in each sample. This graph also shows the time taken for the reaction to finish, this being the time when we could no weeklong see the cross on the paper below the conical flask due to the solution becoming too murky in colour. It can be spy by looking at Graph 1 that, the lower the amount of Na2S2O that is present in the solution, the longer the time taken for the reaction to finish. This occurs because there is a reduced amount of Na2S2O concentration present in the mixture which can react with the HCL.This can also be seen in Graph 2 which shows the affinity between the amounts of Na2S2O concentration to the time required for the reaction to finish. Graph 1 also shows that the greater the amount of water present in the solution the longer it takes for the reaction to finish as the concentration of Na2S2O to HCL is nurture diluted. Thus it can be concluded that our results support the hypothesis that more change state solutions react alacritous than diluted solutions do.The affect on the reaction rate when varying the amount of water and Na2S2O is that more concentrated the Na2S2O and HCL mixture is, the faster the reaction occurs, i.e. the less water that is present to dilute the mixture the faster the reaction occurs. Evaluation Overall the investigation was completed successfully and we achieved our aim of investigating how a change in the concentration of a reactant affects that rate of a chemical reaction. There are a number of factors that can be changed and controlled so that to improve the accuracy of the results. The following things done in the future will friend to ensure that more rel iable data is obtainedUsing a rubber stopper in the conical flask when the HCL was transferred into the conical flask, gas escaped form the top of the flask. If in future tests, this gas was detain inside the flask with the use of a stopper the reaction may engage completed faster. trim human error Starting the timer at the same time in all the reactions would drop helped to increase the accuracy of the results. The timer should have been started either once the full amount of HCL was transferred in the conical flask or should have started when the pouring started.Another variable which could have been controlled was the number of times the conical flask was swirled after the HCL was added. This would have further helped with the accuracy of the data if all the samples were swirled at the same stronghold and the same number of times. Using distilled water this would ensure that the water is pure There might have also been errors with reading the scales on the measuring cylinder as we were reading these to the best of our ability. To be veritable that the exact amount of solution was added an electronic weighing scale could have been used.