COMPASSLearning
RegisterLogin

JEE Main · 2024 · 27 Jan 2024 · Shift 2 · Practical and Analytical Chemistry

WhatsApp Email
The technique used for purification of steam volatile water immiscible substance is:
  1. (A)Fractional distillation
  2. (B)Fractional distillation under reduced pressure
  3. (C)Distillation
  4. (D)Steam distillation✓ Correct

Answer: (D)

Solution

Steam distillation purifies substances that are volatile with steam and immiscible with water, even when they carry non-volatile impurities. When steam is passed through such a mixture, the compound co-distils with the water because the sum of the vapour pressures of water and the compound reaches atmospheric pressure at a temperature below the compound's own boiling point. The condensed vapours separate into two immiscible layers, from which the organic compound is recovered — this is how essential oils, aniline and nitrobenzene are purified.

JEE Main · 2024 · 27 Jan 2024 · Shift 2 · Single correct option

Practise more: all JEE Main PYQs on Practical and Analytical Chemistry →

More JEE Main questions on Practical and Analytical Chemistry

  1. Consider the following reactions.
    (Hot solution)
    …
    JEE Main 2026View solution →
  2. In Carius method, 0.75 g of an organic compound gave 1.2 g of barium sulphate, find percentage of sulphur (molar mass ). Molar mass of barium sulphate is .
    JEE Main 2026View solution →
  3. Sodium fusion extract of an organic compound (Y) with and chlorine water gives violet color to the layer. 0.15 g of gave 0.12 g of the silver halide precipitate in Carius method. Percentage of halogen in the compound …
    JEE Main 2026View solution →
  4. When 1 g of compound ( X ) is subjected to Kjeldahl's method for estimation of nitrogen, 15 was neutralized by ammonia evolved. The percentage of nitrogen in compound is :
    JEE Main 2026View solution →
  5. Identify the correct statements:
    A. Hydrated salts can be used as primary standard.
    B. Primary standard should not undergo any reaction with air.
    C. Reactions of primary standard with another substance should be instantaneous and stoichiometric.
    D. Primary standard should not be …
    JEE Main 2026View solution →
  6. Match List-I with List-II.

    List-I: Functional group (detection)
    (A) Unsaturation (Baeyer's test)
    (B) Alcoholic group (Ceric ammonium nitrate test)
    (C) Aldehyde group (Tollen's reagent)
    (D) Phenolic group ( test)

    List-II: Change observed during detection
    (I) Red co …
    JEE Main 2026View solution →