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Rate Of Reactions Chemestry Essay Research Paper

llWhat does the Concentration have on the rate of reactionWritten by Stephen FosterBrief:To investigate the factors that affect the rate of reaction between magnesium and hydrochloric acid.Introduction:I am to investigate what effects concentration of the reactant (hydrochloric acid) has on the rate of reaction between it and calcium carbonate. Specifically I am to see weather it will have an effect on the amount of the product produced and the time in which it took place.The Definition: The rate of a reaction is usually expressed in terms of a change in concentration of one of the chemicals involved in the experiment. The rate of a reaction is the speed at which reactants are converted into products. Prediction:I predict that with a raise in the concentration of the reactant will result in the increase in the rate of the reaction also that the reverse is also true for a decrease in the concentration, assuming that the conditions of the test are kept fare. I predict this because it conforms with collision theory which describes that the way concentration and surface area of the solid reactant affects the rate of the reaction, by affecting the collisions between particles. Particles react when they collide with sufficient energy to break the bonds holding them together, this is called the activation energy. At a higher concentration collision will become more frequent and thus increasing the rate of reaction, because there are more particles in the liquid.Scientific Reason:I think this will happen because an increase in the number of particles will increase the chances of the particles colliding. This will raise the rate of the reaction and all the decrease the time in which it takes place. Plan:I am to investigate what effects concentration of the reactant (hydrochloric acid) has on the rate of reaction between it and calcium carbonate.In my experiment I will use the following apparatus: Delivery tube, Water bath, Meniscus tube & beaker.There is a certain level of safety concerning this experiment which is directed to the concentration of the Hydrochloric acid (Hcl), so I have taken the precaution of wearing safety glasses and when using the highest concentration 2.0 molars I will use safety goggles because of the increased risk. I am measuring the amount of gas produced.To make the experiment a fare test I will keep all variables the table excluding the Concentration of Hydrochloric acid (Hcl). I think that the amount of gas produced will increase as the concentration of acid is increased. I also think that the time in which the reaction to take place will decrease with the raising in the concentration of the reactant hydrochloric acid.I will be using a long thin glass tube with measurements on the side to measure the gas collected in the experiment. I ve chosen this over other apparatus because it s more accurate in this type of experiment and better designed for measuring gas.I the factors I m investigating are the concentration of Hydrochloric acid, the amount of gas produced at pre set time intervals, the amount of hydrochloric acid used in each experiment & the amount of calcium carbonate used in each separate experiment.One factor I couldn t control was the temperature at the time when the experiment was performed. I can not say without some doubt that the room temperature of which I conducted my experiment was at a constant, this may affect the rate of the reaction as temperature can have an invaluable affect of the rate of the reaction. However I doubt that the room temperature varied a great deal.I will keep the amount of calcium carbonate the same (0.3g) each time I perform the experiment, the quantity of Hydrochloric acid will also be kept the same, I will keep all variables the same except for the concentration of Hydrochloric acid.I will take 8 measurements at 15 second intervals, in total the length of the experiment will be 2 minutes and I shall carry out the experiment 5 times with varying concentrations of Hydrochloric acid. I think that with a raise in the concentration of the reactant will result in the increase in the rate of the reaction also that the reverse is also true for a decrease in the concentration, assuming that the conditions of the test are kept fare because when you increase the concentration of the reactant in this case Hydrochloric acid the number of particles is raised and thus raises the chances of one particle colliding with another and starting a reaction. This will make the reaction more virile and the product will be produced at a faster rate than any other concentration of the reactant lower than the one currently in use. The overall concentration of Calcium carbonate particles remains the same in accordance with my wishes to keep this variable the same, but the concentration of Hydrochloric particles has risen a great deal and raises the chances of particles colliding.

I will try and make my measurements as precise as I can so that my evidence will be much clearer and easier to read. One way of helping this is to keep the gas collecting tube upright so that the readings will appear precisely as possible.Method:I decided to make things simpler by ignoring all but the 120-second result for each experiment. I decided on this one because I thought that it would be most accurate, since the result is greater, so errors become smaller in comparison to the eventual result.The purpose of this experiment is to devise weather there is a link between the concentration of a reactants concentration and the amount of the product produced.Step one is to collect the equipment necessary to perform each experiment, these include:-Beaker, delivery tube, water bath, the different concentrations of hydrochloric acid, Meniscus tube, measuring tubes, clamp, safety goggles & Timer for recording results.Set out the rough guide lines for a table to record your results, make sure that the table covers all the areas necessary to record i.e. Time, Concentration etc Set the apparatus as shown of the diagram. Pay close attention to the Meniscus tube make sure that it stands upright so that in accurate results can be avoided.Fill the water bath with water about two thirds of the way up this will allow you form a seal over the Meniscus tube . This will prevent any gas escaping and tamper with the results.Fill the Meniscus tube with water, fill it so that the measurement reads 0. Form a seal over the bottom of the tube and plunge it into the water bath making sure that no bubbles get into the tube and effect the reading on the tube. After doing so clamp the tube in to place making sure that its horizontal.Measure exactly 0.3g of calcium carbonate and pour it in the conical flask.Also measure 5ml of Hydrochloric acid in a measuring tube ( when doing so use safety goggles).Each time you perform the experiment pay special attention to these measurements as they are the main factors in this experiment and any inaccuracies would effect the eventual results.Pour the acid in the conical flask and quickly seal it with the bung attached to the delivery tube. Immediately after doing this start the Timer as quickly as possible.Record the amount indicated on the Meniscus tube at each time interval. After the 2 minuets are up stop the timer clean out the conical flask and perform the experiment again but this time with the next concentration of acid, repeat this until the 5 acid strengths are completed.Diagram: Equipment:Equipment used in this experiment.Miniscus tubeConical flaskDelivery tubeWater bath0.3g of calcium carbonate5ml of Hydrochloric acidTable of Results:What does the Concentration have on the rate of reactionWritten by Stephen FosterConclusion:I found out that increasing the acidic concentration raises the level of gas produced. It also increased the rate of the reaction, meaning that the product was produced at a faster rate than that of the acidic concentrations lower than the one currently in use.After examining the graph I found out that a distinct pattern exists connecting each experiment together. The weakest concentration of acid produced the least amount of gas after 120 seconds , only 7.3ml of gas was produced. This was true for the rest of the experiment in that the second lowest concentration of Hydrochloric acid produced the second lowest amount of gas, this trend continued for the rest of the experiment with similar differences between the level of gas produced in each experiment except for the highest concentration in which the results did not conform with the pattern that was set by the previous experiments in fact the amount of gas produced after 120 seconds was over three times the amount produced in the last four experiments. In conclusion the amount of gas produced (the product) is dictated by the concentration of the acid, the higher the concentration of acid the higher the amount of gas produced. The results on the graph support my prediction and they also support collision theory which described the collision between particles and how the speed of the reaction is dictated by the surround temperature and the concentration of the reactant. In my experiment I tested for only concentration so my evidence only supports that concentration of the reactant has effect of the rate of the reaction. The evidence I have accumulated and the results from my experiment seems to confirm my prediction however the accuracy of my results can t be assured because gas may of escaped while I was placing the delivery tube bumg on the conical flask.

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