Unknown Orgo Lab Functional Group Tests

Bromine/CCl₄ Test

Test for Alkenes

pos = unsaturation = decolorization

neg = color stays the same

Flame Test (1)

Test for Aromatic Compounds

pos = soot, different color flame

neg = normal fire

Beilstein Test

Test for Alkyl or Aryl Halides

pos = green flame = halogen

neg = normal flame color = no halogen

Silver Nitrate Test

Test for Alkyl or Aryl Halides

pos = immediate precipitate

neg = no precipitate

Chromic Acid Test

Test for alcohols

pos = green/blue change

neg = stayed orange (unless it is tertiary alcohol)

Lucas Test

Test for alcohols

pos = precipitate immediately = tertiary alcohol

neg = no precipitate or for secondary/primary alcohols

Ferric Chloride Test

Test for phenols

pos = blue, purple, red, green color

neg = no color

Bromine - Water Test

Test for phenols

pos = yellow color disappears, pH test strip is pink

neg = stays yellow

2,4-Dinitrophenylhydrazine (DNP) Test

Test for aldehydes and ketones

pos = red, orange, yellow precipitate

• yellow - carbonyl nonconjugated

• orange/red - conjugate carbonyl

neg = no precipitate

Chromic Acid Test (2)

Test for aldehydes and ketones

pos = blue/green color change = aldehyde

neg = no color change, stays orange = ketone

Tollens Test

Test for aldehydes and ketones

pos = silver mirror metal coating or black precipitate = aldehyde

neg = nothing or salt made (?) = ketone

Iodoform Test

test for aldehydes and ketones

pos = pale yellow precipitate = methyl ketone, or loss of brown color = ketone

neg = stay brown (?), no color change = aldehyde

Sodium Bicarbonate Test

Test for carboxylic acids

pos = formation of bubbles

neg = no bubbles formed

Hinsberg Test

Test for Amines

pos = primary = precipitate or crystallizes in NaOH, secondary = insoluble in NaOH and react tertiary = no reaction and insoluble in NaOH

Hydroxylamine / Ferric Chloride Test

Test for Esters

pos = deep red or purple color = ester, test again with hydroxylamine hydrochloride = pos test = phenol

neg - no color change

Iron (II) Hydroxide Test

Test for Nitro Compounds

pos = red-brown or brown precipitate quickly

neg = darkening with greenish color or nothing