Question

as part of a science experiment, jose did a test for starch on a slice of apple and a slice of potato. the yellow-orange iodine solution stayed the same color when it was put on the apple, but it became black on the potato.
why did the iodine solution change color on the potato?
a. the iodine burned the potato and turned it to ash.
b. the iodine mixed with the colors of the potato so it looked black.
c. the iodine reacted with the protein to form a new substance.
d. the iodine evaporated into a gas.

Explanation:

The experiment tests for starch using a yellow-orange indicator (likely iodine solution). Potatoes contain starch, which reacts with iodine to form a blue-black complex. Apples have little starch, so no color change occurs. The color change is due to a chemical reaction forming a new substance.

Answer:

C. The iodine reacted with the potato to form a new substance.