Organic Chemistry Tests

Flashcards for specific chemical tests and their positive results.

Br2/CH2Cl2 (light)

Test for alkanes and alkyl benzenes; positive result: discoloration

Br2/CH2Cl2 (dark)

Test for alkenes and alkynes; positive result: discoloration

cold dilute neutral KMnO4 (Baeyer's)

Test for 1° and 2° alcohols, aldehydes and phenols; positive result: loss of purple color, brown ppt

hot acidic KMnO4

Test for aldehydes and phenols; positive result: loss of purple color, brown ppt

Ag(NH3)2+ (Tollens)

Test for aldehydes and phenols; positive result: silver mirror

Ag(NH3)2+

Test for terminal alkynes; positive result: gray ppt

FeCl3

Test for phenols; positive result: purple complex

2,4-DNP

Test for aldehydes and ketones; positive result: yellow to orange ppt

I2/KI, NaOH

Test for methyl ketones and secondary methyl alcohols; positive result: yellow ppt

a-naphthol in ethanol, H2SO4

Molisch test for carbohydrates; positive result: purple interface

Cu(OH)2 in sodium citrate

Benedict's test for reducing sugars; positive result: brick red ppt

phenylhydrazine/HCl

Osazone test for reducing sugars; positive result: yellow crystals

CuSO4, NaOH

Biuret test for proteins, peptide chains with at least 3 amino acids; positive result: violet complex

ninhydrin

Ninhydrin test for a-amino acids and peptides; positive result: violet compound

Pb(CH3COOH)2, NaOH

Lead acetate test for S-containing amino acids and proteins; positive result: black ppt