Practical investigations

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I am doing the iodine clock test as an investigation. My reactants are sodium thiosulphate, starch, HCl, potassium iodide and hydrogen peroxide. At the end when a starch iodine complex forms is it a coloured organic compound with delocalised electrons, if so is it correct to call it a complex?
Also where can I research what the order of my reaction is with respect to the hydrogen ions?

Jenkin says
 
It certainly doesn't consist of a central metal ion bonded to a number of ligand molecules or ions by lone pairs of electrons, so it isn't a complex in that sense. I think the word complex here means just a complicated species.
 
It is sometimes described as an adsorption complex, suggesting that iodine molecules are concentrated on the surface of starch molecules, but iodide ions are almost certainly involved, as well as the colour is visible at extremely low iodine concentrations. One of my references (Pine, Hendrickson, Cram and Hammond, Organic Chemistry) suggests it is a 'complex' (their word) formed when an I₅^- species is held within the very long, spiral, starch molecule.
 
Igloo adds
 
I agree with Jenkin about the starch iodine complex. The intense blue-black colour formed when starch and iodine interact is not strictly a “complex” with a fixed structure, but is a relatively “loose” clathrate or cage arrangement involving iodine in the form of I₅^- ions being trapped in the coils of the beta amylose molecules of starch.
 
You will find more details at this web site.
 

As for the kinetics of the reaction between iodide ions, hydrogen peroxide molecules and hydrogen ions, the process, according to : this web reference is first order with respect to hydrogen ions.
 

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updated: 10 March 2006