Investigation Into The Relationship Between Temperature Of

Acid And The Rate Of Reaction In The Reaction Of Caco3 And Hcl Essay, Research Paper

Background Information The speed at which reactants are converted into products during a reaction is referred to as its rate. Usually in a reaction, the amount of the product of the reaction is measured to work out the rate of the reaction. In this reaction, the rate will be calculated by the equation: Rate = 1 Time. The Collision Theory states that the rate of reaction depends on how often and how hard the reacting particles collide with each other. In order for a molecular collision to be effective it must have sufficient impact energy to overcome the amount of activation energy needed. (The activation energy is the minimum energy necessary for product to form). The mole theory tells us, by knowing the molarity of the reactants, you can predict how much gas will be produced. We are working with 2M HCl and CaCO3 we are wishing to produce 100cm2 of CO2 we need to work out how many moles in this. One mole of CO2 weighs 44g so 100cm2 will have 2.27 moles. We need the reactants to produce this much gas. The calculations for the mole theory say we would only need 1.42cm2 of the acid in this experiment and 0.44g of CaCO3.The rate of the reaction can be affected by several factors which can be considered variables.Concentration: An increase in concentration means there are more particles. More particles means there will be more collisions. This should increase the reaction rate. Surface Area: When one of the reactants is a solid, the reaction can only take place at the surface of the solid. Breaking the solid into smaller pieces will increase the surface area exposed to the other reactant. This should increase the reaction rate. Temperature: Since temperature is a measure of the motion of particles, increasing the temperature will cause the particles to move faster, giving them more energy. When particles move faster, more collisions occur and the collisions are more violent. This should increase the reaction rate. Catalysts: Catalysts are substances that change the rate of a chemical reaction without being changed in the reaction. Catalysts are most often used to speed up a chemical reaction. They do this by changing the steps needed between the reactants and the formation of the products. If the number of steps can be reduced, the reaction rate should increase. Higher temperatures increase the energy of the collisions, because the particles are made to move faster. Increasing the temperature increases the average kinetic energy of the molecules. Faster collisions are only caused by increases in temperature. Reactions only happen if the particles collide with each other with enough energy at impact. At a higher temperature there will be more particles colliding with sufficient energy to make the reaction occur. This initial energy is known as the activation energy required to break the initial bonds. Equation for this experiment CaCO3(s) + 2HCl(aq.) ————– CaCl2(aq.) + H2O(l) +CO2(g)PlanIn this experiment I intend to do two experiments, in each the apparatus will be set out as shown below. Firstly the acid shall be weakened to only 1M and suitable adjustments to the quantities of these reactants made based on the mole theory. From this we decided to use 10cm3 of acid and an excess of 1g of the marble chips as so the lowering temperature does not affect the amount of gas produced, because, as temperature falls, the molecules have less energy so, the chances of . The acid shall be heated up on the Bunsen burner until it reaches the desired temperature. It will be allowed to rise slightly above the necessary temperature so it is exactly on the correct temp for when it is used. 10cm3 of hydrochloric acid will be measured out and placed into a boiling tube. One gram of calcium carbonate will be added to the boiling tube and the rubber bung stuck into the top. At this the stopwatch will be started. All of the gas produced by this reaction will be taken to the gas syringe by the delivery tubes, where it will gather and push out the plunger as more gas enters. This experiment will be done in two different ways: 1/ with temperatures every 10oC between 10oC and 80oC to investigate the relationship between rate of reaction and acid temperature; 2/ with temperatures doubling each time starting at 5oC going upto 10oC then 20oC etc . This will be to see if the rate time is proportional to temperature. Either way, the experiment shall be done twice and averages taken for the graph as this minimises chance on anomalous results. I will minimise the risk if anomalous results by keeping all the other variables constant by: trying to have all of the calcium carbonate chips the same size; keeping the concentration of acid the same each time and by using the same amounts of each of the reactants for each experiment. To get to the temperatures below room temperature (20oC, 10oC and 5oC) the 10cm3 of acid will be placed in the boiling tube and then into a beaker of ice to lower the temperature. The experiment will be done the same from there onDiagramPredictionI think that the temperature will cause the rate of reaction to increase as it, itself, increases. This is because, as the temperature rises, the molecules become increasingly active and start to become more free they move around at greater speeds causing the chance of an effective collision occurring greater for two reasons: They are moving more and have a greater chance o