The Importance Of Chemical Kinetics

Chemical kinetics is a branch of chemistry which refers to chemical reactions with respect to reaction rates, effect of various variables, re-arrangement of atoms, formation of intermediates and much more (Chung Chieh, 2016).The importance of chemical kinetics is that it provides evidence for the mechanisms of chemical processes and provides a very detailed description of what happens to each molecule —which bonds are broken and formed, and how the three-dimensional shapes of the chemicals changes during the course of a chemical reaction (Keith J. Laidler, 2016).

The Iodine Clock reaction is a prime example of where chemical kinetics can be observed. Iodine Clock reactions refers to a group of reactions which requires the combining of two

In reaction [1] it states that the iodide ions (I) are oxidized by hydrogen peroxide(H2O2 ) in an acidic solution to form triiodide ions (I3 ) and water( H2O) (B. Z. Shakhashiri,1992). Subsequently the triiodide ions (I3 ) are reduced back to iodide ions (I) by thiosulfate ions (S2O3) as indicated in reaction [2] and this forms iodide ions and tetrathionate(S4O6 )(Science Buddies Staff,2015). Reaction [2] is much faster than the reaction of equation [1] as it consumes the triiodide ions(I3 ) as fast as they are formed (B. Z. Shakhashiri,1992). This reaction happens so fast that the triiodide have no time to form a complex with starch, even though the starch is in the reaction mix (Science Buddies Staff,2015). After all the thiosulfate ions have been consumed by the reaction of equation [2], the triiodide ions(I3 ) react with starch to form the blue starch-pentaiodide complex (starch-I5-complex + I- ) in reaction[3] and this is what caused the blue colour at the end of the whole reaction(B. Z. Shakhashiri,1992). Reaction [1] is the rate determining step as it 's the slowest in the overall reaction mechanism, thus increasing the concentration of iodide, hydrogen peroxide, or acid would accelerate the reaction but on the other hand, increasing the thiosulfate concentration will have the opposite effect; it will take longer for the iodine color to appear (B. Z.

The three variables that are to be investigated in this particular experiment are temperature, concentration and a