From the results of the experiment represented in a tabular form above, the hypothesis suggested before carrying out the experiment turned out to be incorrect. The dialysis tubing was not permeable to all the three solutions- glucose, starch and Iodine (Potassium Iodide). Rather, the tubing was permeable to glucose and iodine but not starch. Table 2 showing the results for the Benedict’s and Iodine Test Sample Appearance after testing agent is added Benedict’s I 2-KI 1 Water (control) Light blue Clear light yellow 2 Glucose Brick red color Clear light yellow 3 Lactose Penny brown color Clear light yellow 4 Sucrose Dark blue Clear light yellow 5 Hydrolyzed Sucrose Dirt color Clear light yellow 6 Starch Light blue Violet 7 ... Iodine Test. Using iodine to test for the presence of starch is a common experiment. A solution of iodine (I 2) and potassium iodide (KI) in water has a light orange-brown color. If it is added to a sample that contains starch, such as the bread pictured above, the color changes to a deep blue.

Sep 03, 2012 · Comparison of iodine test results from an incomplete (left) and complete (right) conversion. The exact colour of the complete reaction will vary depending on the colour of the wort, but what you will observe in all cases is a "dilution" of the colour of the iodine, without any darkening or formation of particulates. The iodine reagent used for the starch test is usually prepared by dissolving iodine in water, after potassium iodide has been added to improve iodine's solubility. The resulting compound is a triiodide ion complex that has the ability to produce the intense blue coloration.