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Introduction

________________ 2.0 Abstract: From the experiment, we become understand about dynamic equilibrium and Le Chatelier?s principle. Besides, we able to observe the change of an equilibrium when the concentration of a reactant or product is altered. We also know how to predict the effect of concentration changes on chemical equilibrium. This report shows, whenever a system in equilibrium is disturbed the system will adjust itself in such a way that the effect of the change will be reduced or moderated. Changing the concentration of a chemical will shift the equilibrium to the side that would reduce that change in concentration. The chemical system will attempt to partly oppose the change affected to the original state of equilibrium. In turn, the rate of reaction, extent, and yield of products will be altered corresponding to the impact on the system. The principle is used to manipulate the outcomes of reversible reactions, often to increase the yield of reactions. 3.0 Introduction: Introduction: In a chemical reaction, chemical equilibrium is the state in which both reactants and products are present in concentrations which have no further tendency to change with time. This state results when the forward reaction proceeds at the same rate as the reverse reaction. A common misconception is that the concentrations are equal, which is incorrect. Equilibrium is when the forward and reverse reactions occur at the same rate. Le Chatelier is one of the central concepts of chemical equilibria. Le Chatelier's principle can be stated as follows: A change in one of the variables that describe a system at equilibrium produces a shift in the position of the equilibrium that counteracts the effect of this change. ...read more.

Middle

The tube is agitated and observations are recorded. ________________ 1. The Chromate-bichromate Equilibrium 5 mL of a 0.1 M potassium chromate (K2CrO4) solution is added to a 4" test tube. Its colour is observed and recorded. 6 M nitric acid (HNO3) solution one drop at a time is added to this solution, until a distinct change is noted. Observations are recorded. Then, 6 M sodium hydroxide (NaOH) solution one drop at a time is added to the same test tube, until once again a distinct change has been observed. Again, observations are recorded. 1. The Bismuth Chloride-Water Equilibrium Add 2 mL of distilled water is added into, a 6" test tube. Agitate the tube of water, which consist of a small crystal of bismuth chloride (BiCl3) and record observation. In the next mixture, 12 M of hydrochloric acid (HCl) is added at a time, while agitating the test tube. Observation is then recorded. Later on, added a drop of water at a time while agitating the test tube till there?s a distinct change. Observation is then recorded as well. 1. The Cobalt (II) chloride Equilibrium: 5 drops of a 1 M cobalt (II) chloride (CoCl2) solution, is added in a 4" test tube. Observation is then recorded. 12 mL of hydrochloric acid (HC1) is dropped into the mixture at a time while agitating it. Observation is then recorded. Finally, a drop of water at a time while agitating the test tube. Observation is also then recorded. ...read more.

Conclusion

Thus, the concentration of A increases again and more C and D will react to replace the A that has been removed. When decrease the concentration of A, the position of equilibrium moves to the left. When one of the products is removed as soon as it was formed, the position of equilibrium will move to the right to replace it. If the product keeps being removed, the equilibrium position would keep on moving rightwards and turn the chemical reaction into a one-way reaction. ________________ 6.0 Conclusion: In a nutshell, we are able to understand dynamic equilibrium and Le Chatelier's Principle throughout the experiment. We are able to define dynamic equilibrium in which the reaction rate of the forward reaction is equal to the reaction rate of the backward reaction. Besides, we are able to observe the change of an equilibrium when the concentration of a reactant or product is altered. For example, if the concentration of a reactant is increased, the equilibrium will shift in the direction of the reaction that uses the reactants, so that the reactant concentration decreases in order to maintain equilibrium. In contrast, if the concentration of a reactant is decreased the equilibrium will shift in the direction of the reaction that produces the reactants, so that the reactant concentration will increases. Furthermore, we are able to predict the effect of concentration changes on chemical equilibrium. If the concentration of a substance is changed, the equilibrium will shift to minimise the effect of that change. Moreover, we are able to prepare various molar concentration of solution by using suitable formula. ________________ 7. ...read more.

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