KVV E-Modules

Tannins are generally soluble in which of the following solvents?

A: Chloroform B: Hexane C: Water and Ethanol D: Petroleum ether

The characteristic taste of tannins is:

A: Astringent B: Sour C: Pungent D: Bitter

What is the typical molecular weight range of tannins?

A: 50–100 Da B: 1000–10,000 Da C: 200–500 Da D: 500–3000 Da

Which of the following compounds do tannins form complexes with?

A: Sugars only B: Alkaloids, proteins, and heavy metals C: Fats and oils D: Simple alcohols

In the Ferric Chloride test, a blue-black color indicates the presence of:

A: Hydrolyzable tannins B: Condensed tannins C: Complex tannins D: Pseudotannins

The Goldbeater’s skin test is used to:

A: Distinguish between alkaloids and flavonoids B: Detect pseudo-tannins C: Confirm true tannins D: Measure protein concentration

Which test uses gelatin and NaCl to confirm the presence of tannins?

A: Ferric chloride test B: Matchstick test C: Lead acetate test D: Gelatin test

A pink/red color on the tip of a matchstick in the Matchstick test indicates:

A: Presence of gallic acid B: Presence of catechin C: Presence of alkaloids D: Presence of chlorogenic acid

What is the observation in the Lead Acetate test for tannins?

A: Brownish red solution B: Blue-black precipitate C: White precipitate D: Yellow-green fluorescence

In the Alkaline Reagent Test, the yellow color that disappears upon acidification indicates:

A: Hydrolyzable tannins B: Flavonoid tannins C: Pseudo-tannins D: Alkaloid presenc