Question

A student set up a test-tube containing starch, water and amalyse. How could the student test whenever the amalyse had digested all the starch? A) add biuret solution B) add dilute hydrochloric acid C) add iodine solution or D) weight the test-tubes and contents before and after the experiment..

Answer 1

Answer:

The answer is - Add iodine solution

Answer 2

The correct option is- C) add iodine solution.

• An iodine test is done to detect the presence of starch in a food item or solution. The addition of iodine solution will change the colour of substance to blue-black if it contains starch. In the absence of starch, there will be no change in colour.
• Hence, to detect whether the amylase had digested all the starch, the student should add iodine solution as it will help him to detect the presence of starch.