Formal Report Experiment 3 Up Diliman Chem 26.1

CHEMICAL KINETICS: THE IODINE CLOCK REACTION

J. ANG

NATIONAL INSTITUTE OF GEOLOGICAL SCIENCES, COLLEGE OF SCIENCE

UNIVERSITY OF THE PHILIPPINES, DILIMAN, QUEZON CITY 1101, PHILIPPINES

DATE SUBMITTED: 27 APRIL 2014

DATE PERFORMED: 23 APRIL 2014

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ABSTRACT

This paper is a study on the effects of different experimental conditions on the rates of reactions. The aim of this study is to form an idea of how certain factors affect the rates of reactions. This paper may be used as a basis for future studies regarding rates of chemical reactions. In the performed experiment the Iodine clock reaction was utilized and multiple tests were performed, exposing the chemical reaction to different initial concentrations, different temperatures and the addition of a catalyst, the time it took for the reactions to reach endpoint were recorded to establish how these different factors affect the rate of the reaction. It was concluded from the results that the reaction followed a second order rate law, with both initial concentrations of thiosulfate and iodide having first order, the rate of reaction was also found to be directly affected by temperature, higher temperature resulted in a faster reaction rate, and the addition of a catalyst greatly increased the rate of reaction.

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INTRODUCTION

Chemical Kinetics is the study of the speed at which chemical reactions occur and how different experimental conditions affect it. Such factors that can affect the rate of a reaction are temperature, concentration, and the presence of a catalyst. The Iodine clock reaction is an experiment formulated to visualize these effects. In this experiment, the reaction between Persulfate (S2O82-) and Iodide (I-) is observed and the reaction will be exposed to different experimental conditions. The balanced reaction is shown below in figure 1.

S2O82- + 2I- → 2SO42- + I2

Figure...