What color are lima beans(split) supposed to turn when exposed to iodine?
Jul.16, 2011 in
Lima
Question by Keith H: What color are lima beans(split) supposed to turn when exposed to iodine?
I did a lab today. We added iodine to lima beans that we split to find if they were a monocot or dicot. Our group observed that the bean turned a darkish brown, but it doesn’t seem right. Any help with this experiment would be appreciated.
Best answer:
Answer by Jan
Well, the starch in the bean should turn darkish blue when you apply the iodine. Did you allow the bean to soak up moisture from damp paper towels overnight?
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July 16th, 2011 at 7:30 pm
The lima bean contains starch which reacts with iodine to produce a pale blue to black color. If there was only a small amount of starch, a brownish color would appear. If the color was more the color of iodine, then the starch test was negative.