To test for the presence of starch, iodine can be used. A positive reaction results in a black color. A dialysis bag filled with starch solution and secured on both ends is placed in iodine solution. After 30 minutes the dialysis bag appears black. Based on this information, what most accurately describes what happened?
According to the information given before the example in the question and considering the fact that the bag was secured on both ends before being placed in the solution, provided that there were no holes on the surface of the bag, the iodine solution could have diffused through the bag into the starch solution hence the color change to black after 30 minutes.
