Question

a slice of bread give a positive iodine test. however,if the slice is thoroughly chewerd the test is negative​

Answer 1

Answer:

Answer: When you chew the bread saliva digests the starch present in it hence it gives negative test. Reason why a slice of bread after chewing gives negative iodine test: ... Iodine gives blue color when it reacts with raw bread due to the presence of starch in it.

Please make me branlist

Answer 2

This shows that digestion of starch begins in the mouth.

Iodine test is used for detecting presence of starch. After thorough chewing, the enzyme present in Saliva digests the starch presence in the slice of bread. So, starch no longer remains in the slice; it gets converted to maltose.

Hence, the experiment proves that digestion of carbohydrates begins in the mouth.