Sunday, March 8, 2020

Rates of Reaction Essay Example

Rates of Reaction Essay Example Rates of Reaction Essay Rates of Reaction Essay The task that we were given was to measure the rates of reaction. I chose to measure it by changing the concentration of the reactant which will enable me to use collect a wide range of data.StrategyOur reactants were hydrochloric acid and magnesium whilst our products were hydrogen and salt.Hydrochloric acid (HCl) + Magnesium (Mg) Hydrogen (H) + Salt (MgCl)To achieve the different concentration of hydrochloric acid we used a 2 molar base concentration and then diluted it with water. For example, the 1M acid was 10ml HCl and 10ml H2O. As we were using 2M, we chose to test eight different concentrations, at 0.25 intervals as this would provide us with the necessary range of data and also, with an equal amount between each, it would make it easier for us to draw conclusions.The method that we used was: we filled up the plastic bowl with water and then also filled a measuring cylinder with water and turned it upside down with its end in the water of the bowl. It was held in place with a clamp stand. We had to ensure that there were no air bubbles in the cylinder or the measurements that we took would be inaccurate because it wouldnt have begun with zero gas in the cylinder. We placed the end of the tube and bung into the cylinder and measured out the appropriate amount of hydrochloric acid and poured it into a boiling tube. Next, we cut a strip of magnesium down to 2cm long and put it into the boiling tube, placing the bung in immediately and starting the stopwatch.We chose to see how long it took to produce 15cm3 of hydrogen because, during our preliminaries, when our original measurement was 20cm3, sometimes not enough hydrogen was produced.The measuring equipment that we used was chosen for the specific measurements that it could provide to measure out the water and acid we used a pipette as it could easily remove or add a very small measurement to exactly make up the 20ml that was the total measurement of our acid and water solution. The technique for collec ting the gas was reliable. The same person completed the same specific job in the practical which meant that the reaction times of the person with the stopwatch wasnt different each time and one person didnt shake the boiling tube to give the particles more energy to collide when they were placing the bung on, all of which would make the tests slightly more unreliable.Collecting DataWe took careful care to keep any interfering factor under control throughout the practicals by recognising them during the preliminaries that we conducted. These included the exact concentration of the acid, the exact length of the magnesium, the speed with which the bung was placed on and the temperature of the room (and consequently the solution). We were able to easily control the former three with little problems but the latter was much harder to manage. The measurements were correct to the closest millilitre and milligram that was feasibly possible as we used measuring cylinders and rulers that offe red the highest level of accuracy.In the preliminaries, we chose the person who was most suited to continually placing the bung on and as they were able to get a feel for the speed and the reactions that were required during the introductory experiments they were able to place it on at a consistent speed. This at least improved the reliability of the experiments. The temperature of the room was out of our control so the only thing that we were able to do was try and complete the tests in one session as the temperature wouldnt have varied greatly. However, we were unable to do that so instead we continued the experiments on a day which was about the same temperature.The range of our data covered 2M, which was the most that we able to do. The values tested were: 0.25M (2.5ml HCl/17.5ml H20); 0.5M (5ml HCl/15ml H20); 0.75M (7.5ml HCl/12.5ml H20); 1M (10ml HCl/ 10ml H20); 1.25M (12.5ml HCl/7.5 ml H20); 1.5M (15ml HCl/5ml H20); 1.75M (17.5 ml HCl/ 2.5ml H20) and 2M (20ml HCl). In total, we conducted twenty-four experiments as we repeated each concentration three times to ensure accuracy and reliability in the results. Also, if there were any anomalies it would have allowed us to recognise the fault almost immediately instead of only realising when we compared all the data after the practical aspect was finished. Thankfully, we did not receive any anomalies.

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