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Dance Case

Essay by   •  December 1, 2012  •  Essay  •  365 Words (2 Pages)  •  1,375 Views

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Clock reactions are the unique kind of reactions discovered by Hans Heinrich Landolt in 1886. In the clock reaction two colorless solutions of f compounds are mixed; after mixing nothing happens at the first moment. However, after a few seconds the solution suddenly changes its color. There are various kind of clock reaction one of them is the Iodineclock reaction. The Iodineclock reaction was discovered by Hans Heinrich Landolt in 1886. In iodine clock reaction two colorless solutions are mixed; one act as repressor usually vitamin C and other act as catalyst generally liquid starch and at first there is no change in color of the solution because no reaction occurs. After a short time interval, the solution rapidly turns to black. The reaction is termed as the clock reaction because the time taken by the reaction can be change by changing the concentration of vitamin C. In this experiment, the kinematics of Iodineclock reaction was studied, more precisely the effect of change in concentration of vitamin C on the time taken by iodine to turn the given solution of starch and hydrogen dioxide to black is studied.

The different concentration of vitamin c is added to the solution of Iodine, which finally is added to the solution of Hydrogen peroxide, and the starch. Ions from the Hydrogen Peroxide reduce the Iodine into Iodide ions and iodide ion react with starch to form black color. Time taken by the liquid to turn dark blue is observed. The starch turns the iodine blue and hence act as the catalyst in contrast, Vitamin C keeps it from turning blue and hence act as repressor.

The result showed that as the concentration of vitamin c decreases the time taken by the reaction that is the time taken by the solution to turn blue black decreases. The reason for this is that time taken by the reaction to convert the solution into blue happens at different intervals because different chemicals concentration reacts at different speeds. As the concentration of the vitamin c decreases the ability of present vitamin c to keep the solution colorless decreases and starch easily overcome the effect of vitamin c and turn the solution into blue black.

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