Looking for classes? Ksquare Career Institute, Bengaluru →
Distinguishing tests of functional groups
Concepts tested here
- Characteristic reactions
All Questions
2010 AIPMT-MAINS 1 question
-
Match the compounds given in List-I with their characteristic reactions given in List-II. Select the correct option.
Pick the matching item from Column II for each row.
Column I
- a. $CH_3CH_2CH_2CH_2NH_2$
- b. $CH_3C\equiv CH$
- c. $CH_3CH_2COOCH_3$
- d. $CH_3CH(OH)CH_3$
Column II
- i. Alkaline hydrolysis
- ii. With KOH (alcohol) and $CHCl_3$ produces bad smell
- iii. Gives white ppt. with ammoniacal $AgNO_3$
- iv. With Lucas reagent cloudiness appears after 5 minutes
Correct answer: a → ii, b → iii, c → i, d → iv
a. $CH_3CH_2CH_2CH_2NH_2$ is a primary amine; warmed with $CHCl_3$ and alcoholic KOH it gives an isocyanide with a very offensive smell (carbylamine reaction): a-ii.
b. $CH_3C\equiv CH$ is a terminal alkyne with an acidic hydrogen; with ammoniacal $AgNO_3$ (Tollens' reagent) it gives a white precipitate of silver propynide: b-iii.
c. $CH_3CH_2COOCH_3$ is an ester; it undergoes alkaline hydrolysis (saponification) to give the sodium salt of the acid and methanol: c-i.
d. $CH_3CH(OH)CH_3$ is a secondary alcohol; with Lucas reagent (conc. HCl + anhydrous $ZnCl_2$) cloudiness appears after about 5 minutes: d-iv.
Correct match: a-ii, b-iii, c-i, d-iv.
