2007-06-21 02:51:50 · 10 answers · asked by sareenaferoz 1 in Science & Mathematics ➔ Chemistry
The 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.
This reaction is the result of the formation of polyiodide chains from the reaction of starch and iodine. The amylose, or straight chain portion of starch, forms helices where iodine molecules assemble, forming a dark blue/black color. The amylopectin, or branched portion of starch, forms much shorter helices and iodine molecules are unable to assemble, leading the colour to be of an orange/yellow hue. As 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.
Iodine solution will also react with glycogen, although the color produced is browner and much less intense.
2007-06-21 03:03:03 · answer #1 · answered by Ricardo H 2 · 0⤊ 0⤋
Amylose Iodine Test
2016-12-12 17:08:50 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Iodine will indicate the presence of amylose by turning blue-black. Amylose is a starch produced by many plants.
2007-06-21 02:57:28 · answer #3 · answered by Diminati 5 · 0⤊ 0⤋
In forensics iodine is a very useful chemical in bringing up fingerprints. Just like how bleach is used for bringing up blood stains.
2007-06-21 02:56:50 · answer #4 · answered by James K 2 · 0⤊ 0⤋
In addition to starch, one can detect or titrate anything that iodine will oxidize. For example, amount of SO2 in water. SO2 gets oxidized to SO3, while I2 gets reduced to 2I-. You follow the disappearance of the yellow brown color of I2.
2007-06-21 03:00:42 · answer #5 · answered by steve_geo1 7 · 0⤊ 0⤋
Starch
2007-06-21 02:53:21 · answer #6 · answered by Meg...Out of Hybernation 6 · 0⤊ 0⤋
No Starch= Yellowish clear
Starch= Blue/black
**Boiling Benedict's solution is for glucose**
2007-06-21 02:56:11 · answer #7 · answered by Anonymous · 0⤊ 0⤋
Thyroid function
2007-06-21 03:01:02 · answer #8 · answered by Charly S 1 · 0⤊ 0⤋
iodine turns startch blue/black.
2007-06-21 02:54:09 · answer #9 · answered by Maya's_Mama 3 · 0⤊ 0⤋
i think it is used to test for starch..... i think.
2007-06-21 02:55:02 · answer #10 · answered by Anonymous · 0⤊ 0⤋