What is the positive reaction between Starch and Iodine?
347240
The positive reaction between Starch and Iodine is called IODINE TEST.\nThe Iodine test is used to test for the presence of starch. Iodine solution - iodine dissolved in an aqueous solution of potassium iodide - reacts with starch producing a deep blue-black color.Starch is broken down or hydrolyzed into smaller carbohydrate units, the blue-black color is not produced. Therefore, this test can determine completion of hydrolysis when a color change does not occur.\n\nIodine solution will also react with glycogen although the color produced is browner and much less intense.
288705
Iodine is a vital nutrient.  It is necessary for the function of the thyroid gland.  Since not everyone eats shellfish, which is a natural source, someone decided it would be a good idea to add it to table salt.\n\nSodium iodide is given for radiation exposure.  There are some communities near some nuclear reactors where the people are given sodium iodide tablets to take in case of a radiation release.  Although I am not sure of the exact mechanism, I believe that it is given because the iodine can bind with certain radioactive isotopes you may have inhaled (or otherwise gotten into your body) and help you eliminate it from your body before it can do a lot of harm.
9839
If the bottle says 3.1 % v/v this the bottle is not labeled correctly.  Iodine is a solid and the label should have said 3.1 % w/v.  This means that there is 3.1 grams of iodine in every 100 mL of solution.\nThe 1 % titratable iodine means that the free (not bound to other substances) iodine is at least one percent of the solution.  Iodine concentration is often determined by titration with sodium or potassium thiosulate.\nYour bottle of Iodine is probably an aqueous (in water) solution.  Tinctures are made by dissolving iodine in denatured ethyl (grain) alcohol or 70 % isopropyl (rubbing) alcohol.
566534
There are three possible answers:\n\n1,1-diiodoethylene, which is I2C=CH2\ncis-1,2-diiodoethylene, which is IHC=CHI, with both iodines on the same side\ntrans-1,2-diiodoethylene, which is also IHC=CHI, with the iodines on opposite sides of the molecule
646111
You can turn it black with an iodine solution, then turn it back with sodium thiosulphate solution. Neat trick.
111777
http://en.wikipedia.org/wiki/Starch
120628
To detect starch just add some drops of iodine to the substance you want to test. Iodine is yellow/brown and turns dark blue/black in the presence of starch. As for fat, just rub your substance if it is a solid on a piece of paper or place a drop of it on the paper if it is a liquid. If the substance leaves a translucent stain on the paper( stain that does not evaporate) then it has fat.
748741
2K + I2 -> 2KI\n\nBa + S -> BaS\n\nMgBr2 + MnI6 -> No Reaction\n\nC7H16 + H2O -> No Reaction\n\n2KI + Br2 -> 2KBr + I2
82368
U get precipitate of Lead Iodide. The reaction is already mentioned!!!!\n\nPb(NO3)2 (aq) + 2KI (aq) --> 2KNO3 (aq) + PbI2 (s)
649333
When an analyte that is a reducing agent is titrated directly with a standard iodine solution, the method is called "iodimetry".\n\nWhen an analyte that is an oxidizing agent is added to excess iodide to produce iodine, and the iodine produced is determined by titration with sodium thiosulfate, the method is called "iodometry".
762139
Starch is a natural polymer.  It won't dissolve until you start breaking the bonds joining the monomer units (beta glucose, if I recall correctly).
48015
I assume this is a an experiment.\nI guess you mean '... inluence of ON amylase?'\n\nThe protein amylase is an enzyme which will change the macromolecule starch into sugars.\n\nIodine solution will turn blue-black when mixed with starch, but remain golden brown when mixed with sugars. The iodine solution can indicate if any starch remains after being mixed with an amylase solution.\n\nYou will firstly need to discover the concentration of amylase to use to change starch into sugars within a convenient period of time - say 5 - 10 minutes at room temperature.\n\nSet up water baths at a range of temperatures and put measured amounts of amylase solution and of starch solution into tubes in the baths. Leave them to reach temperature.\n\nAdd the measured quantities of amylase to the starch solutions. Stir.\n\nImmediately remove a drop of each mixture and mix with a drop of iodine (prepare iodine drops on a spotting tile).\n\nRepeat this every 30 seconds - yes, you'll have to be quick and organised.\n\nYour results will show whether or not temperature affects the rate of reaction of amylase on starch.
731401
Correct.\nD. when delta G is positive the reaction is non-spontaneous
872398
it forms amylose if there is beta1,4 glycosidic linkage &also it forms amylopectin if the molecule forms beta 1,4 and beta 1,6 glyocosidic linkage.\nits a trihydroxyalcohol\nhydrocarbon chain\nfattyacid and glycerol\nit is a high energy giving biomolecule&helps in lipid metabolism
949244
The normal phase of iodine is solid but it can easily vapour at room temperature. \n\nThis the detailed information describing iodine:\n\nIodine is a bluish-black, lustrous solid. It volatilises at ambient temperatures into a pretty blue-violet gas with an irritating odour.\n\nIt forms compounds with most elements, but is less reactive than the other halogens, which displace it from iodides. Iodine exhibits some metallic-like properties. It dissolves readily in chloroform, carbon tetrachloride, or carbon disulphide to form beautiful purple solutions. It is only slightly soluble in water. Iodine compounds are important in organic chemistry and very useful in medicine and photography. Lack of iodine is the cause of goitre (Derbyshire neck). The deep blue colour with starch solution is characteristic of the free element. It is assimilated by seaweeds from which it may be recovered, and is found in Chilean saltpetre, caliche, old salt brines, and salt wells.
88453
Simple Suagrs can be tested with Benidicts Soultion which turnes from blue to yellow to orange to brown in the presense of a simple sugar when heated in a hot water bath.  Polysaccharides can be tested with iodine which turns purple in the presence of starchs.  There really is no simple test for disaccharides but they can be ruled out by testing for both simple sugars and polysaccharides.  Lipids are not carbohydrates but they can be tested for by a simple paper bag that becomes translucent when smeared with a lipid(like eating potato chips and touching a piece of paper) or with Sudan III which forms red rings on a piece of filter paper.
952630
water is smallest, then glucose , then starch is bigger.\n\nI do not know what IKI is , nor how big it's molecule is, so Ido not know where to slot it in.