Hands-On Labs, Inc.
Lab Report Assistant
This document is not meant to be a substitute for a formal
laboratory report. The Lab Report Assistant is simply a summary of the
experiment’s questions, diagrams if needed, and data tables that should be
addressed in a formal lab report. The intent is to facilitate students’ writing
of lab reports by providing this information in an editable file which can be
sent to an instructor.
Exercise 1: Starch and
Data Table 1.Benedict’s Reagent Data.
Data Table 2. Lugol’s Iodine Data.
Starch Present in
In each of the two
tests (starch and sugar) a positive and negative control was used. What was the
positive control in each of the tests and what was the negative control.
Explain your answers.
Did the Benedict’s
test for reducing sugars net a positive or negative result for milk? Research
the sugar content of milk and the definition of a reducing sugar to explain if
your result is what you would expect.
Based on your
results, is sugar and/or starch present in your Unknown? Use your results to
explain your answer.
Exercise 2: Proteins and
Table 3. Biuret’s Reagent Data.
Protein Present in
Data Table 4. Lipid Observations.
Lipid Present in
Review the Data Tables in Exercises 1 and 2.
Compare the results of the Unknown for all tests to the results for the various
known samples to determine the identity of the Unknown. Explain the identity of
the Unknown using your experiment results in the exercises to help explain and
support your answer.
Eggs are known to
contain cholesterol which is a lipid. Did your experiment results indicate a
presence of lipids in the albumin solution? Think about this result and where
cholesterol is present in eggs to explain how your results support or reject
cholesterol in eggs. How could you test this? Explain the experiment that you
would perform to test this.