Qualitative test for starch

• 1 - add a few drops of iodine solution to some starch dissolved in water in a test tube labelled A. Iodine is a red/yellow in colour
• 2 - Add a few drops of iodine solution to a second test tube labelled B containing just water
• 3 - Note any colour changes
• Results - the solution in test tube A changed from red/yellow to blue black. The solution in test tube B stayed red/yellow
• Conclusion - Iodine changes from red/yellow to blue back in the presence of starch