Iodine Clock Reaction Essay

Reaction Kinetics: The Iodine Clock Reaction

Kinetics is the study of the rates of chemical reactions. A reaction rate describes the reaction’s speed, it is the rate at which the starting materials of a reaction (reactants) react and transform into the final produced materials (products). The greater the reaction rate, the less time required for reactants to be converted to products. Understanding the factors and conditions influencing reaction rates of is of fundamental importance in industrial chemistry where the production of chemicals must be efficient and economical to maximise profits.

The collision theory is used to predict reaction rates and proposes that reaction rate is directly proportional to the number of effective collisions

The values of the reaction orders determine the dependence of the reaction rate on concentration of the respective reactants and generally have a following value: 0, 1, -1, or 0.5. The Reaction Orders (“x” and “y”) will be determined experimentally by measuring the initial rate of five experiments with varying concentrations of one reactant independently of the concentration of the other reactant (B). This allows us to determine the dependence of the rate on the concentration of persulfate and the numerical value of the Reaction Order with respect to reactant persulfate.

This investigation involves conducting the iodine clock reaction, a reaction between sodium persulfate and potassium iodide. During the experiment, a colourless solution of potassium iodide and a solution of sodium persulfate, starch and thiosulfate will be combined into a beaker to later react into a blue-black complex. The elapsed time from when colourless solutions are combined to the colour change is dependent on the reactant concentrations of sodium persulfate and potassium iodide. Experiments will be conducted by systematically varying the concentrations of persulfate and iodine. The times recorded will be utilised to determine the rate of reaction and