Module 3 Lab 2: Sugars and Fats
Purpose
This lab will test for the sugar and/or fat content of 7 separate solutions.
Hypothesis
Part 1: If 10% sucrose solution, 1% sucrose solution, onion juice, 1 % starch solution, and DI water are tested for sugar content, then 1% sucrose solution will be shown to have a minimal amount of sugar, the 10% sucrose solution and onion juice will have a moderate amount of sugar, and the 1% starch solution and DI water will have no sugar.
Part 2: If DI water, evaporated milk, and vegetable oil are tested for fat, then the DI water will be shown to have no fat and the vegetable oil and milk will have fat.
Materials:
Test tube rack, 4-5 test tubes, transfer pipet, protective glasses, 3 pieces of paper bag, DI water, evaporated milk, 10% sucrose solution, 1% sucrose solution, onion juice, 1 % starch solution, vegetable oil, and Benedicts reagent.
Methods:
First the test tubes must be labeled with a wax pencil. Then add 3 mls of each substance. Next add 5 drops of the Benedicts reagent to each test tube, place the test tubes into boiling water for 10 minutes, remove the test tubes using a test tube holder, and record the results. For the second test, label three pieces of paper bag, then place one drop of each solution on the paper bag. After 15 minutes see if there is any oily residue left on the bag
Results
Part 1: Sugar
Solution
Result
DI Water
Blue
1% Starch
Blue
1% Sucrose
Blue/Green
10% Sucrose
Yellow
Onion Juice
Dark Brown