EXP 5: FORMALDEHYDE AND AROMATIC ALDEHYDE

formation of brick red ppt

positive result in Fehling's test

formaldehyde
HCHO

simplest aldehyde

benzaldehyde
C6H5CHO

an arenecarbaldehyde that consists of benzene bearing a single formyl substituent

acetone
CH3COCH3

the simplest and smallest ketone

Methanal

IUPAC name of Formaldehyde

Phenylmethanal

IUPAC name of Benzaldehyde

propanone

IUPAC name of Acetone

CuO

copper (II) oxide

Schiff's test

used to test the presence of Aldehydes

magenta solution

positive result for Schiff's test

CH2O & C6H5CHO

gave a positive result in Schiff's test

Red magenta fuchsin[C20H19N3Cl•HCl] is decolorized by SO2

Schiff's reagent

C6H4(OH)2

resorcinol

red flocculent ppt (formaldehyde only)

positive result in resorcinol test

H2SO4

added in resorcinol test to form a layer at the bottom

AgNO3

silver nitrate

formation of silver mirror on the walls of the test tube

positive result for Tollen's test

CH2O & C6H5CHO

gave a positive result for Tollen's test

Ag(NH3)2OH

Tollen's reagent

ammonium formate - HCOONH4

product of formaldehyde on Tollen's test

ammonium benzoate - C6H5COONH4

product of benzaldehyde on Tollen's test

does not dissolve in hot water

result of gelatin in CH2O and H2O

dissolves in hot water

result of gelatin in H2O only

gelatin sheet

used in testing the action of formaldehyde on protein proteins

True

Proteins don't dissolve in aldehydes.
True or False

CuSO4, Rochelle's salt (sodium potassium tartrate), NaOH

Fehling's solution is a mixture of...

Fehling's test

test used to distinguish ketones and aldehydes

deep blue

color of Fehling's solution

CH2O

gave a positive result in Fehling's test

Cu(OH)2 - copper(II) hydroxide

Fehling's test reagent

HCOOH - formic acid & Cu2O - copper(I) oxide

product of formaldehyde on Fehling's test

Copper(I) oxide or cuprous oxide

the brick red precipitate in Fehilng's test

formation of white crystals

result of auto-oxidation of benzaldehyde

benzoic acid

the white crystals in auto-oxidation of benzaldehyde

NaHSO3

sodium bisulfite

formation of white ppt

result in addition of sodium bisulfite

CH3C(OH)(SO3Na)CH3 - acetone sodium bisulfite

name of the white ppt

Carbonyl group (C=O)

The formation of the white ppt in addition of sodium bisulfate indicates the presence of a ____________________.

H2NNHC6H5 - 2,4-dinitrophenyl hydrazine

added to acetone to form phenylhydrazone

CH3C(CH3)NNHC6H5 - acetone 2,4-dinitrophenyl hydrazone

name of the yellow-orange ppt

NaOH & I2

reagents in iodoform test

iodoform test

test for ketones

yellow ppt is formed

result in iodoform test

gas

Formaldehyde is __________ at room temperature.

formalin

a 37-40% solution of formaldehyde in water

pungent irritating odor

odor of formaldehyde

acetone

a liquid and neutral substance

ethereal fragrant mintlike odor

odor of acetone