Virtual Lab: Testing for Organic Molecules
By: Sarah Vandorpe
Problem: How can indicators be used to test for the presence of different organic
molecules?
Background Information: In this activity I will be testing for two different types of
organic molecules: glucose and protein. This table shows the indicators you can use
to test for the presence of various common organic substances.
Hypothesis: I think that indicator can be used to test the presence of different organic
molecules by the color change that can occur with different mixtures.
Design: > glucose
 starch
 protein
 fat/oil
Pre-Lab Work: (already done above.)
Materials and Equipment: > all of the ingredients in “Design.”
> WebCT Science 931 Assignment.
Procedure:
1. Testing for Glucose with Benedict’s Solution.
2. Testing for Protein with Biuret Solution.
Data:
Final Colors Using Indicators
Substance Tested
Benedict's Solution
Biuret Solution
corn starch
No color change.
No color change.
glucose
Yes, brick red.
No color change.
water
No color change.
No color change.
gelatin
No color change.
Yes, purple.
oil
No color change.
No color change.
Analysis:
1. Which five substances above contained each of the following molecules and
explain why.
a) glucose - glucose
b) protein – gelatin.
2. Explain how glucose is identified by using Benedict's solution.
2. Glucose was identified in Benedict’s solution by the solution turning a brick red
color.
3. Explain how Biuret solution identifies protein.
3. In Biuret solution identifies protein by the color of the solution going purple.
Conclusion: We now no that if an organic molecule turns purple when it contains
protein and red when glucose is in it.
Bibliography: I used WebCT and Science Focus 9.