The Crumbling Taj Essay Example for Free

The Crumbling Taj Essay The reaction rate, however, should decrease as the experiment progresses because as the reaction time increases the number of hydrochloric acid molecules present will decrease as they have been reacted to form water calcium chloride and carbon dioxide. The additional water and calcium chloride present as the experiment progresses should decrease the rate of reaction because of decrease in concentration. This should make a graph of the reaction curved as the reaction rate slows down. Kinetic theory is based on the assumption that chemical reactions take place as a result of reacting particles colliding successfully. Successful collisions need a sufficient amount of energy. Particles that posses more kinetic energy than the activation energy are able to react more successfully. The reacting particles all have different kinetic energies due to collisions hanging their speeds. Maxwell and Boltzmann presented the distribution in kinetic energies for two temperatures (high and low) in graphs called distribution curves on which the areas under the curves past the points called energy barriers represent the number of kinetic energies. The bigger the area under the curve, the greater the number of particles with a certain energy that will promote a chemical reaction. Hotter particles have extra kinetic energy after surmounting the number of collisions in unit time. These collisions are more likely to be successful as there would be more than enough energy for them. Although I will not be looking at the factor of TEMPERATURE, I can extend my investigation and experiment the effects of temperature on the rate of reaction. HYPOTHESIS FOR EXPERIMENT 1 COUNTING BUBBLES Counting bubbles is an experiment which I personally think is not very fair. There may be many mistakes in counting the number of bubbles produced for five continuous minutes and so the experiment would not be accurate. Although this experiment isnt so accurate, I think that the results will still show a trend in the pattern of results. I predict that if the concentration of the HCl is doubled then the experiment will happen twice as fast. HYPOTHESIS FOR EXPERIMENT 2 COLLECTING GAS OVER WATER By putting more particles into the reaction, the chance of them colliding increases and so the rate increases. Concentration is a variable that is continuous and independent. I shall test this variable by observing the rate at which hydrogen gas collects over water against the concentration of hydrochloric acid used with CaCO3. I predict that by doubling the concentration of the acid, the rate of reaction will also double. The higher the concentration, the higher the rate of reaction. HYPOTHESIS FOR EXPERIMENT 3 COLLECTING GAS IN A SYRINGE This experiment is very similar to experiment 2 (collecting gas over water) but this experiment is the most accurate out of the three that I will be carrying out. I predict that I will have a very similar type of results and graphs as in experiment 2. I predict that the graph will have more better and accurate trend lines in the graphs showing a curved line of best fit. The higher you raise the concentration the more the particles will collide therefore corrosion of the marble will occur. Plan for the investigation. I will ensure that the goggles are worn throughout the experiments. Care will be taken not to spill any of the acid. Glass will be handled with care to prevent breakages and cuts. If any sort of accident occurs amends will be made with the help of trained technicians. Large volumes of acid will not be carried around to reduce the risk of a spillage. Containers will be kept well away from edges of the benches. Low molar concentration of hydrochloric acid will be used for safety. FAIR TEST To perform a fair test I will do as follows: In the experiment I will measure each substance accurately. I will carry out the experiment at the same room temperature of 20oc each time. I will wash the conical flask with distilled water after each experiment to make sure that there isnt any solution left over from the previous experiment. I will have to stay alert when counting bubbles and will have to concentrate hard. I will also repeat the test again and take the average of the two results to get an average set of results which will be more reliable. By following my fair testing the results will hopefully come out accurate. I will be alert and take the timings accurately for each of the experiments. METHOD FOR EXPERIMENT 1 COUNTING BUBBLES. This is how I will be carrying out my 1st experiment to find out the rate of reaction between marble and hydrochloric acid: When doing my experiments I will use the same procedure throughout. I will first get the necessary equipment that will be needed and will set it up as show below. I will then get 30ml of 0. 1M hydrochloric acid and will put it into the conical flask. To make sure the volumes of acid and water were right we will measure the volumes of each in a measuring cylinder to be accurate. To make sure the mass of marble chips are right we would measure them on the electronic balance to one decimal place. I will then get 2grams of marble chips (roughly the same size) and I will gently put the marble chips into the solution of hydrochloric acid and will spontaneously close the conical flask with the delivery tube that is attached to a bung at the end. As soon as I close the top of the flask, I will start the stopwatch and I will start counting the bubbles, which will be coming out from the test tube. I will record the number of bubbles produced each minute up to five minutes. The bubbles that will be produced will indicate how much CO2 is being given off by the reaction between CaCO3 and 2HCl. I will carry out this experiment again for Distilled water, 0. 5, 1. 0, 1. 5 and 2 molar to see how the concentration affect the rate of reaction. I will keep the amount of marble chips and hydrochloric acid the same for every test I carry out so it would be fair. At the end I will also carry out this experiment on distilled water so I can compare the two substances. In this experiment I will have to concentrate all the time as I will have to count the bubble for five minutes and will have to make sure that I dont miss out on counting a single bubble. After the experiment is over, I will carry out the experiment again to confirm my results and to make sure that I was counting the bubbles correctly. This picture shows how I am going to set-up my experiment and I am going to count the bubbles that come out of the test tube. METHOD FOR EXPERIMENT 2 COLLECTING MEASURING GAS This is how I will be carrying out my 2nd experiment to find out the rate of reaction between marble and hydrochloric acid: When doing my experiments I will use the same procedure throughout. I will first fill the tub with tap water about half way up and fill the measuring cylinder with water and then turn the measuring cylinder upside down into the tub of water so the cylinder would still be filled with water. By doing this, we will create a slight margin of error because some of the water will be displaced when doing this although it will be very little. Then we will clamp the measuring cylinder in place. We will change the size of the cylinders; however, this will not make the test unfair. We then will put the delivery tube under the cylinder so the air from the experiment could displace the water. To make sure the volumes of acid and water were right we will measure the volumes of each in a measuring cylinder to be accurate. I will then get 30ml of 0. 1M Hydrochloric acid and put it into the conical flask. To make sure the mass of marble chips are right we would measure them on the electronic balance to one decimal place. As soon as we put the Marble chips and the acid in the conical flask and close it with the bung which will be attached to a delivery tube; we will immediately start the stopwatch. We will see how long it takes (In seconds) for the measuring cylinder to fill up with 100cm3 of Carbon Dioxide gas. We will carry this experiment out on a range of different concentrations of Hydrochloric acid. I will be carrying out this experiment on 0. 5M, 1. 0M, 1. 5M and 2. 0M to see how the concentrations affect the rate of reaction. I will also use distilled water to compare it against the hydrochloric acid. After the experiment is over I shall carry out a retest to confirm my results and I will take the average out of the two results. Below it show exactly how the experiment was set up. METHOD FOR EXPERIMENT 3 SYRINGE TEST This is how I will be carrying out my 3rd experiment to find out the rate of reaction between marble and hydrochloric acid: When doing my experiments I will use the same procedure throughout. I will first get the necessary equipment that will be needed and will set it up as show below. In this experiment I will again experiment the time it will take for the syringe to fill up with 100cm3 of Carbon Dioxide gas. Although this experiment will be very similar to Experiment 2, this will be more accurate as the equipment used will be more appropriate. I would assume the results in this test to be very similar to Experiment 2 so I will change the amount of Marble chips and the volume of the Hydrochloric acid to experiment what different it makes. I will used 5 grams of marble chips and 50 cm3 of Hydrochloric acid in this test but will used the same range of concentrations which are, 0. 1M, 0. 5M, 1. 0M, 1. 5M, 2M and will also use distilled water. I will do the same, starting of with 0. 1M Hydrochloric acid and put it into the conical flask. As soon as we put the Marble chips and the acid in the conical flask and close it with the bung which will be attached to a delivery tube; we will immediately start the stopwatch. We will see how long it takes (In seconds) for the measuring cylinder to fill up with 100cm3 of Carbon Dioxide gas. After the experiment is over I shall carry out a retest to confirm my results and I will take the average out of the two results. Table of Results for the method of counting the bubbles. Mass of marble /g Concentration of HCl in 30cm3 / M Time In Mins Bubbles collected Expt. 1 Bubbles collected Expt. 2 Bubbles collected Average Initial temperature / oC 2g Distilled water 1 2 3 4 5u.