Carboxylic Acid (–COOH)

AIM – To test the presence of carboxylic acid in the given organic compound.

Preliminary Test:-

Experiment Observation Inference
Added bromine water to solution No Effect Compound is saturated
Or Or
Pink colour of Bromine water changed to colourless. Compound is unsaturated.
Added drop of blue Litmus to solution. Solution turned Red. Carboxylic Acid may be present.

Confirmatory Test:-

Experiment Observation Inference
Added sodium bicarbonate to solution. Gas with brisk effervescence evolved. Carboxylic acid confirmed.

Chemical Equations:-

R3C-CR3 + Br2 –> No Effect

         OR

R2C=CR2 + Br–> BrR2C-CR2Br

 RCOOH + NaHCO3 –> RCOONa + H2O + CO2

You can also get Class XII Practicals on BiologyPhysicsChemistry, and Physical Education.

Amine (−NH2 )

AIM – To test the presence of amine in the given organic compound.

Procedure:-

Experiment Observation Inference
LITMUS TEST

Organic compound + few drops of red litmus solution.

Red litmus turns blue Amino group present.
 SOLUBILITY TEST

Organic compound + 1-2 ml of diluted HCl. Shake well.

Organic compound dissolves. Amino group present
 CARBYLAMINE TEST

Organic compound + CHCl3 + Alc.KOH. Heat

An obnoxious smell is obtained. Primary amine present.
AZO DYE TEST

Dissolve organic compound in diluted HCl and cool in ice. Add ice cold NaNO2 solution to it. Mix well. Add ice cold solution of β- naphthol + NaOH.

A red or orange dye is obtained. Primary aromatic amino group present.


Chemical
 Equations:-

1. R-NH2 + HCl → R- NH3+Cl
    amine                    amine salt     

2. R-NH2 +  CHCl+ 3KOH → R- N≡ C + 3KCl + 3H2O
                                                             Isocyanide or Carbylamine
                                                                    
3. NaNO2 + HCl → HNO2 + NaCl     

4. ArNH2 + HNO2 + HCl  → Ar- N+≡ NCl + 2H2O
    Aromatic                                      Aryldiazonium chloride
1amine                                       (stable between 0- 50C)

 β- naphthol (draw structure)  + Ar- N+≡ NCl → (draw structure of the azo dye obtained) + NaCl + H2O

RESULT: : (ON RULED SIDE )  Amino present in the given organic compound.

You can also get Class XII Practicals on BiologyPhysicsChemistry, and Physical Education.