Please answer all these 3 questions. 1. How does the starch-iodide paper tell yo
ID: 567166 • Letter: P
Question
Please answer all these 3 questions.
1. How does the starch-iodide paper tell you if excess hypochlorite is present? what is happening chemically? (starch turns blue in the presence of I2 ???
2. Draw the products we can expect when borneol reacts with each of these compounds ( nitrous acid, sulfuric acid, phosporic acid ) ???
3. Give an example of an E2 reaction. what are the similarities and the differences between your example and the elimination reaction that occurs in the oxidation of borneol??
Explanation / Answer
1) the concentration of sodium hypochlorite depends on the age of the solution, we wanted to make sure there was excess oxidant.
- to avoid this we could have used calcium hypochlorite which is stable and can be stored at room temp without decomposition
- turns black because of the complex of starch and iodine that is produced from the oxidation of the iodide ion by the hypochlorite ion.
chlorine gas which comes from the hypochloriteas is produced from the oxidation of isoborneol.
Using iodine to test for the presence of starch is a common experiment. A solution of iodine (I2) and potassium iodide (KI) in water has a light orange-brown color.