Organic Molecules

Prelab for Organic Molecule lab
Write out answers to these questions before coming to lab. I may collect your papers or give
you a short “open-homework” quiz .
Sugar Test - (note: Benedict's solution is pale blue. )
1. When Benedict’s solution is mixed with a sugar, what is the range of colors that you might
expect to see?
2. What color will a solution be if there is no sugar present?
3. Look at the list of substances that you will be testing for sugars. Which is one substance that
you predict to test negative(has no sugar) ?
Starch Test
4. Lugol's Iodine is what color?
5. When starch and Lugol's iodine are combined, what color will you see?
6. When Lugol's iodine is placed in water, will the color be blue-black?
7. Which of the substances you are testing will test positive for starch?
Lipid test - this is really a test for fat.
8. Of the substances that you will be testing, which substance do you predict to test positive for
9. Which substance are you pretty sure will not test positive for fat?
Protein Test
10. Which substance that you are testing do you predict will test positive for protein?
11. What color will a solution be if protein is present?