TESTS FOR DISTINGUISH REACTIONS
1. ALDEHYDE:
a) Tollen’s Test(Aliphatic/Aromatic aldehydes)
RCHO+2[Ag(NH3)2]++ 3OH-→RCOO- +Ag++ 2H2O + 4NH3
(Silver mirror)
b) Fehling’s Test: (Only for aliphatic aldehydes)
RCHO+2Cu++ 3OH- →RCOO- + Cu2O+ 3H2O
(Red brown ppt)
2. CARBOXILIC ACIDS:
RCOOH + NaHCO3 → RCOONa +H2O + CO2 (Brisk effervescence)
3. Alcohol: (a) Aliphatic alcohol (Lucas Test)
b) Phenol:
6C6H5OH + FeCl3→[Fe(C6H5O)6]3- + 3HCl + 3H+
Violet Ferric phenoxide complex
4. IODOFORM TEST:
A) CH3-CO- B) CH3 -C-
OH
A) CH3-CO-
CH3CHO + 3I2 +4NaOH→ CHI3+ 3H2O + 3 NaI + HCOO
Yellow ppt
CH3COCH3 +3I2+ 4NaOH→CHI3+3H2O+ 3NaI+ CH3COONa
B) CH3 CH-
OH
CH3CH2OH+ 4I2+6NaOH→CHI3 +5H2O + 5NaI +HCOONa
Yellow ppt
CH3CH(OH)CH3 + 4I2 + 6NaOH → CHI3 + 5H2O + 5NaI + CH3COONa
5. Amines:
a) Aliphatic amines: Reaction with benzenesulphonyl chloride (Hinsberg’s reagent)
C6H5SO2Cl + 2HNC2H5 → C6H5SO2HNC2H5 + HCl
Soluble in alkali
C6H5SO2Cl+ HN(C2H5)2 → C6H5SO2-N(C2H5)2 + HCl
Insoluble in alkali
C6H5SO2Cl + N(C2H5)3→ No reaction
b) Aromatic amines:
Orange dye
QUESTIONS ASKED IN PROVIOUS 10 YEARS:
1. Iodoform test is not given by
a) ethanal b) ethanol c) pentan-2 one d) pentan-3-one (2020)
2. Out of CH3CH2COCH2CH3 and CH3CH2CH2 COCH3 which gives iodoform test? (2020)
3. Which of the following reagent is used for the Hinsberg’s Test of amines?
a) C6H5COCl b) CH3COCl c) C6H5SO3H d) C6H5SO2Cl
DISTINGUISH BETWEEN
ALCOHOL, PHENOL AND ETHERS
1. Phenol and cyclohexanol (2023)
2. Ethanol and phenol (2017, 2019)
3. Propanol and 2 -methylpropan-2-ol (2017)
4. Phenol and 1-propanol (2019) (3 mark question)
Ethanol and dimethylether
1-propanol and 2-methyl-2-proponal
5. Ethanol and propanol (2019)
ALDEHYDES, KETONES AND CARBOXYLIC ACIDS:
1. Ethanal and propanal (1/5,2018)
2. Ethanal and proponone (1/2,2018, 2023)
3. Benzaldehyde and acetophenone (Delhi,2015; 1/5, 2017)
C6H5COCH3 and C6H5CHO (1/5,2015; 1/2,2016)
4. CH3CH2CHO and CH3CH2COCH3 (1/5, 2015; 1/2, 2016)
5. Propanal and butan-2-one (1/5, Foreign 2014)
6. Benzaldehyde and benzoic acid Propanal and propanone (1/5, Delhi 2014; 1/5 2016; 1/5,
2020, case study based 2023)
7. Butanal and Butan-2-one (2/5, 2017)
8. Benzoic acid and ethylbenzoate (1/3,Delhi 2017;
1/5,2015; Fore, 2014)
9. Benzoic acid and phenol (2/5, 2017)
10.Benzoic acid and benzoldehyde (2/5, Delhi 2014, 2020)
11. Pentan-2-one and pentan-3-one (Term II, 2021-22)
12. CH3CH2CH2COCH3 and CH3CH2CH2CHO
Ethanal and ethanoic acid (2/3, 2023)
14. Ethanol and benzaldehyde
Acetone and acetic acid (2021)
15. CH3- CH¿CH-CO-CH3 and CH3 - CH2 -CO -CH¿CH2 (2020)
16. CH3COOH and HCOOH (1/2, 2016)
AMINES:
1. (CH3)2NH and (CH3)3N (Foreign 2014)
2. Aniline and ethanamine (2/3, 2020, 2019)
Aniline and N-methylaniline (2/3, 2020)
3. CH3CH2NH2 and (CH3CH2)2 NH
Aniline and CH3NH2 (2/5, 2020)
4. Aniline and N.N-Dimethylaniline (1/5, 2018)
5. CH3NH2 and (CH3)2NH
6. Describe a method for the identification of C2H5NH2, (C2H5)2 NH
and (C2H5 )3N. Also write the chemical equation for the reactions
involved.
7. How can you distinguish between CH3CH2NH2 and (CH3CH2)2NH by Hinsberg test?
Extra questions:
1. Distinguish: HCOOH and CH3COOH
HCOOH +2[Ag(NH3)2]+ +2OH-→ 2Ag + CO2 + 2H2O + 4NH3
Note: Compounds give positive test for Tollen’s test
RCHO, ArCHO, ἀ-hydroxyketone, formic acid, hemiacetal
2. Chlorobenzene and benzylchloride (Phenylchloride)
C6H5CH2Cl aq NaOH
→
C6H5CH2OH + NaCl
NaCl + AgNO3→AgCl (White ppt)
C6H5Cl aq NaOH
→
X
