Experiment No. 01
AIM: To detect the presence of carbohydrates in each sample using the Molisch test.
Principle: The Molisch test is based on the reaction between carbohydrates and α-naphthol,
resulting in a purple or violet ring formation at the interface when sulfuric acid is added. This
test is used as a general test for the presence of carbohydrates.
Materials Required:
• Chemicals:
o α-Naphthol solution (Molisch reagent),Concentrated
sulfuric acid (H₂SO₄) , Distilled water
o Carbohydrate sample (e.g., glucose, sucrose, or starch)
• Glassware and Equipment:
o Test tubes o Test tube rack o Pipettes o Droppers o Stirring
rods o Safety goggles o Lab coat
o Gloves
Procedure:
1. Preparation of Test Solution:
o Dissolve a small amount of the carbohydrate sample (approximately 1-2 mg)
in 1-2 mL of distilled water in a test tube. If the sample is solid, ensure it is
fully dissolved before proceeding.
2. Addition of Molisch Reagent:
o Add 2-3 drops of α-naphthol solution to the test solution in the test tube. Mix
gently.
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AIM: To detect the presence of carbohydrates in each sample using the Molisch test.
Principle: The Molisch test is based on the reaction between carbohydrates and α-naphthol,
resulting in a purple or violet ring formation at the interface when sulfuric acid is added. This
test is used as a general test for the presence of carbohydrates.
Materials Required:
• Chemicals:
o α-Naphthol solution (Molisch reagent),Concentrated
sulfuric acid (H₂SO₄) , Distilled water
o Carbohydrate sample (e.g., glucose, sucrose, or starch)
• Glassware and Equipment:
o Test tubes o Test tube rack o Pipettes o Droppers o Stirring
rods o Safety goggles o Lab coat
o Gloves
Procedure:
1. Preparation of Test Solution:
o Dissolve a small amount of the carbohydrate sample (approximately 1-2 mg)
in 1-2 mL of distilled water in a test tube. If the sample is solid, ensure it is
fully dissolved before proceeding.
2. Addition of Molisch Reagent:
o Add 2-3 drops of α-naphthol solution to the test solution in the test tube. Mix
gently.
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