p.1
Molisich Test for Carbohydrates
What does the Molisch test detect?
The presence of carbohydrates based on the dehydration of sugars by sulfuric acid.
p.5
Amino Acid Detection Tests
What does the Ninhydrin Test detect?
The presence of ammonia, primary/secondary amines, or amino acids.
What is the expected result of Fehling's test for reducing sugars?
Red precipitate for Glucose, Fructose, Xylose, Lactose, Maltose.
What does Tollen's test detect?
Aldehydes (reducing sugars) based on the reduction of silver ions to metallic silver.
What is the expected result of Barfoed's test for disaccharides?
Little to no precipitate for Lactose, Maltose.
What happens to cottonseed oil when mixed with distilled water?
Cottonseed oil will not dissolve and remains on top because it is non-polar.
How does bromine water react with unsaturated fatty acids?
Bromine water reacts by breaking the double bonds in unsaturated fatty acids.
p.3
Cholesterol Detection Tests
What color change occurs in the Salkowski test for cholesterol?
Cholesterol reacts with sulfuric acid to produce a red or pink color.
p.5
Amino Acid Detection Tests
What is the expected result of the Lead Acetate Test for sulfur-containing amino acids?
Formation of a black precipitate of lead sulfide.
p.5
Amino Acid Detection Tests
What is the expected result of Millon’s Test?
Formation of a red solution or precipitate.
p.4
Protein Detection Tests
What is the primary element detected in proteins during the nitrogen detection test?
Nitrogen in their amino groups.
p.3
Cholesterol Detection Tests
What color change indicates the presence of cholesterol in the Liebermann-Burchard test?
The formation of a blue-green color upon acid addition indicates cholesterol presence.
What is the expected result of reducing sugars in Benedict's test?
Red or orange precipitate for Glucose, Fructose, Xylose, Lactose, Maltose.
p.4
Protein Detection Tests
What characteristic odor indicates the presence of ammonia during the nitrogen detection test?
Pungent, sharp ammonia smell.
p.4
Coagulation and Precipitation of Proteins
What effect do mineral acids have on proteins?
Cause protein precipitation by neutralizing charges.
What is the expected result of Barfoed's test for monosaccharides?
Red precipitate for Glucose, Fructose, Xylose.
What does a semi-translucent spot on paper indicate?
It indicates the presence of fats and oils.
p.5
Amino Acid Detection Tests
What is the expected result of the Xanthoproteic Test for albumin?
Formation of a yellow precipitate, which turns orange with NH₄OH.
What is the purpose of Barfoed's test?
To differentiate between monosaccharides and disaccharides.
p.1
Molisich Test for Carbohydrates
What types of sugars can be detected by the Molisch test?
Monosaccharides, disaccharides, and polysaccharides.
What is the expected result when cottonseed oil is tested with Hanus iodine solution?
The iodine color fades faster due to a higher number of double bonds in cottonseed oil.
What is the purpose of Benedict’s test?
To detect reducing sugars in a solution.
What does Fehling's test detect?
Reducing sugars by the reduction of copper(II) ions to copper(I) oxide.
What is the general solubility characteristic of lipids?
Lipids are generally hydrophobic (insoluble in water) and soluble in organic solvents.
p.4
Protein Detection Tests
What happens to pH paper when ammonia gas is present?
Turns blue due to its basic nature.
p.4
Coagulation and Precipitation of Proteins
What is the result of protein coagulation when alcohol is added?
Formation of a precipitate.
p.1
Anthrone Test for Carbohydrates
What is the expected result of the Anthrone test?
A blue-green complex indicating the presence of carbohydrates.
What is the expected result when cottonseed oil is mixed with ether?
Cottonseed oil dissolves completely, forming a larger translucent spot.
p.1
Anthrone Test for Carbohydrates
How does the Anthrone test work?
It hydrolyzes carbohydrates into monosaccharides and then catalyzes their dehydration to form furfural derivatives.
p.5
Amino Acid Detection Tests
What does the Xanthoproteic Test detect?
Amino acids containing phenolic or indolic groups like phenylalanine, tyrosine, and tryptophan.
What is a false-positive result in the context of reducing sugar tests?
Reactions with drugs like penicillin, isoniazid, streptomycin, salicylates, and p-aminosalicylic acid.
What is the expected result of Tollen's test for reducing sugars?
Silver mirror for Glucose, Xylose, Lactose.
p.1
Molisich Test for Carbohydrates
What color indicates a positive result in the Molisch test?
A violet or purple ring at the interface.
p.4
Protein Detection Tests
What is the expected odor when proteins are burned?
Burning hair or feathers, characteristic of nitrogenous compounds.
p.4
Coagulation and Precipitation of Proteins
What is the expected result of heating proteins?
Formation of a white solid (coagulated protein).
p.5
Amino Acid Detection Tests
What color indicates a positive result in the Ninhydrin Test?
Purple or blue-violet color (Ruhemann’s purple).
p.5
Amino Acid Detection Tests
What does Millon’s Test specifically react with?
Tyrosine, an amino acid with a phenolic group.
