Q.

The chemical formula of Lucas reagent is

see full answer

Start JEE / NEET / Foundation preparation at rupees 99/day !!

21% of IItians & 23% of AIIMS delhi doctors are from Sri Chaitanya institute !!
An Intiative by Sri Chaitanya

a

NaOH+CaO

b

Anhy.ZnCl2/HCl

c

HNO2

d

C6H5SO2Cl

answer is A.

(Unlock A.I Detailed Solution for FREE)

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Detailed Solution

Lucas reagent formula is a combination of anhydrous zinc chloride (ZnCl2) dissolved in concentrated hydrochloric acid (HCl).

Purpose and Applications of Lucas Reagent

The Lucas reagent formula is primarily used to distinguish between primary (1°), secondary (2°), and tertiary (3°) alcohols based on their reactivity. The test involves observing the reaction of alcohols with the Lucas reagent to form alkyl halides, which appear as a turbidity in the solution.

Key Reactions

  • 1° alcohols: Show no turbidity or a very slow reaction.
  • 2° alcohols: Show turbidity within a few minutes.
  • 3° alcohols: React immediately, forming turbidity instantly.

Preparation of Lucas Reagent

The Lucas reagent formula is prepared by dissolving anhydrous ZnCl2 in concentrated HCl. The mixture forms a solution that is highly reactive and suitable for testing alcohols.

Example Reaction

When a tertiary alcohol reacts with the Lucas reagent:

(CH3)3COH + HCl → (CH3)3CCl + H2O

Watch 3-min video & get full concept clarity
score_test_img

Get Expert Academic Guidance – Connect with a Counselor Today!

whats app icon