Purification and Characterization of Organic Compounds MCQs [Organic Chemistry]

MCQs-based on questions and answers on Purification and Characterization of Organic Compounds in organic chemistry.

Which of the mentioned steps is/are involved in structure determination of an organic compound?

  1. Qualitative and quantitative analysis of elements present
  2. Purification of compound
  3. Determination of molar mass
  4. All A, B, and C steps

Question’s Answer: All A, B, and C steps


Which of the mentioned techniques is involved in compounds? purification of organic

  1. Solvent extraction
  2. Sublimation
  3. Distillation
  4. All A, B, and C

Question’s Answer: All A, B, and C


Which of the mentioned technique is helpful and used to Separate two liquids?

  1. Sublimation
  2. Distillation
  3. Recrystallization
  4. Filtration

Question’s Answer: Distillation


Sugar and common salt in a mixture can be separated with the help of _______.

  1. Sublimation
  2. Distillation
  3. Crystallization from solution in ethanolb
  4. Chromatography

Question’s Answer: Crystallization from solution in ethanol


An impure sample of camphor, contaminated with sand, can be purified with which of the following techniques?

  1. Distillation
  2. Chromatography
  3. Steam distillation
  4. Sublimation

Question’s Answer: Sublimation


The violet colour in the Lassaigne’s test of sulphur is due to which of the following?

  1. FeCl3
  2. Nag[Fe(CNS)6]
  3. Na[Fe(CN)5NOS]
  4. Fe [Fe(CN)6]3

Question’s Answer: Na[Fe(CN)5NOS]


Identify the wrong statement in context of  crystallization.

  1. It is an important procedure for purifying solids
  2. The impurities are removed by filtering the solution
  3. Crystals are separated by filtration
  4. In crystallization method, the solid is dissolved in a solvent in which it is soluble at all temperature

Question’s Answer: In crystallization method, the solid is dissolved in a solvent in which it is soluble at all temperature


The function of boiling the sodium extract with conc.HNO3 before testing the halogens is

  1. To make solution clear
  2. To destroy CN and S2- ion
  3. To bring common ion effect
  4. To make the solution acidic

Question’s Answer: To destroy CN and S2- ion


Two solids X and Y have appreciable different solubility in water but their m.p. are very close. The mixture X and Y can be separated by which of the following?


  1. Sublimation Fractional crystallization
  2. Distillation
  3. Specific rotation

Question’s Answer: Fractional crystallization


What are the stationary and mobile phases in paper chromatography?

  1. Liquid/solid
  2. Solid/liquid
  3. Liquid/ liquid
  4. Liquid/gas

Question’s Answer: Liquid/ liquid


In Dumas method, the, volume of the gas collected is equivalent to _________  gases set free from the compound.

  1. Ammonia
  2. N₂
  3. CO₂
  4. NO

Question’s Answer: N₂


Carbon and hydrogen are estimated by which method?

  1. Kjeldhal’s method
  2. Dumas method
  3. Liebig’s method
  4. Carries method

Question’s Answer: Liebig’s method


Phosphorus is detected by fusing the organic compound with extraction with H₂O followed by _____.

  1. HNO3
  2. H₂SO4
  3. Ozone
  4. Sodium peroxide

Question’s Answer: Sodium peroxide


Which technique is used to determine the molar mass of organic acid?

  1. Cryoscopy
  2. Potentiometry
  3. Conductometry
  4. Refractometry

Question’s Answer: Cryoscopy


The simplest formula of a compound containing 50% of element X (at. wt = 10) and 50% Y (at. wt = 20) is ______.

  1. X₂Y
  2. XY
  3. XY2
  4. X2Y3

Question’s Answer: X₂Y


Beilstein test is helpful and used for ______.

  1. Carbohydrates
  2. Amides
  3. Organic halides
  4. Anilides

Question’s Answer: Organic halides


What is the most suitable method of separation in mixture of o- and p-nitrophenol?

  1. Chromatography
  2. Steam distillation
  3. Sublimation
  4. lon-exchange

Question’s Answer: Steam distillation


Essential oils are purified by which of the mentioned methods?

  1. Crystallization
  2. Sublimation
  3. Steam distillation
  4. Fractional crystallization

Question’s Answer: Steam distillation


Presence of nitrogen in organic compound is tested as

  1. Nitrogen gas
  2. CN
  3. NO
  4. NH3

Question’s Answer: CN


When FeSO, is added in the sodium extract the compound formed is

  1. Only Na [Fe(CN)6]
  2. Only Na2SO4
  3. Only Fe(OH)2
  4. Mixture of all these

Question’s Answer: Mixture of all these


Which of the mentioned compound will not give the Lassaigne’s test of nitrogen?

  1. H₂NCONHNH₂ HCI
  2. CH₂-N-N-CH₂
  3. H₂NCONH₂
  4. H₂N-NH, 2HCI

Question’s Answer: CH₂-N-N-CH₂


In organic analysis Lassaigne test is employed for which group?

  1. Nitrogenous functional groups only
  2. Halogens based functional groups only
  3. Elemental analysis
  4. Sulfur based functional groups only

Question’s Answer: Elemental analysis


In Lassaigne test, nitrogen is identified by detecting the __.

  1. Amine
  2. Cyanide
  3. Nitride
  4. None of these

Question’s Answer: Cyanide


In Lassaigne test, sulphur is identified by detecting the ______.

  1. Sulphide
  2. Thiols
  3. Sulphate ion
  4. None of these

Question’s Answer: Sulphide


For ____, Chloroform detection of layer test is employed.

  1. Amines
  2. Carbonyls
  3. Halogens
  4. Amines

Question’s Answer: Halogens


Bromine test is done to detect _______.

  1. Carbohydrates
  2. Unsaturation
  3. Carbonyls
  4. Amides

Question’s Answer: Unsaturation


Aromatic alcohols can be identified by which test?

  1. Dinitrophenyl Hydrazine test
  2. Baeyer test
  3. Natural ferric chloride test
  4. Ring test

Question’s Answer: Natural ferric chloride test


Which is not a test for detection of carbonyl compounds?

  1. Dinitrophenylhydrazine
  2. Molisch test
  3. Schiff test
  4. Tollen test

Question’s Answer: Molisch test


Which one is not a test for detection of amine?

  1. Diazotization test
  2. Nitrous acid test
  3. Lucas test
  4. Carbylamine test

Question’s Answer: Lucas test


Which one is not a test for detection of carbohydrates?

  1. Chloroform test
  2. Molisch test
  3. Iodine test
  4. Charring with sulfuric acid

Question’s Answer: Chloroform test


Which one is a test for detection of phenols?

  1. Molisch test
  2. Ferric chloride test
  3. Benedict test
  4. Conc. H₂SO4

Question’s Answer: Ferric chloride test


Formation of oily drops by treating organic compound with soda lime indicates ______ .

  1. Carboxylic acids.
  2. Phenols
  3. Amides
  4. Anilides

Question’s Answer: Anilides


Evolution of ammonia gas by treating organic compound with soda lime indicates

  1. Amides
  2. Phenols
  3. Anilides
  4. Carboxylic acids

Question’s Answer: Amides


Which of the mentioned halide gives yellow ppt with AgNO3 solution?

  1. Chloride
  2. Bromide
  3. Fluoride
  4. Iodide

Question’s Answer: Iodide


Which of the mentioned halide gives white ppt with AgNO3 solution?

  1. Bromide
  2. Chloride
  3. Iodide
  4. Fluoride

Question’s Answer: Chloride


When N and S are present together, then addition of AgNO2 gives

  1. Orange ppt
  2. Yellow ppt
  3. White ppt
  4. Black ppt

Question’s Answer: Orange ppt


S in organic compound can be confirmed by treating sodium extract with acetic acid and lead acetate solution. This gives

  1. White ppt
  2. Black ppt
  3. Orange ppt
  4. Yellow ppt

Question’s Answer: Black ppt


We will conclude that it is class_______, If the aqueous solution of the compound turns the blue litmus red?

  1. Acidic class
  2. Neutral glass
  3. Basic class
  4. None of A, B, and C

Question’s Answer: Acidic class


We will conclude that it is class_______, If the aqueous solution of the compound turns the red litmus blue?

  1. Neutral class
  2. Basic class
  3. Acidic class
  4. None of A, B, and C

Question’s Answer: Basic class


We will conclude that it is class_______, If the organic compound is soluble in cold 5 -10% NaHCO3 solution with evolution of gas.

  1. Carboxylic acids
  2. Amines
  3. Phenols
  4. Neutral class

Question’s Answer: Carboxylic acids


If the organic compound is insoluble in cold 5 10% NaHCO3 but soluble in 5-10%NaOH solution, it indicates

  1. Amines
  2. Phenols and weak acids
  3. Carboxylic acids
  4. Neutral class

Question’s Answer: Phenols and weak acids


If the organic compound is insoluble in cold 5 10% NaHCO3 and 5-10% NaOH solution, but soluble in 5 % HCl, it indicates

  1. Phenols and weak acids
  2. Amines
  3. Carboxylic acids
  4. Neutral class

Question’s Answer: Phenols and weak acids


If the organic compound is insoluble in All A, B, and C solutions, but soluble in cold concentrated sulfuric acid, at indicates

  1. Phenols and weak acids
  2. Amines
  3. Carboxylic acids
  4. Neutral class

Question’s Answer: Neutral class


If the water insoluble compound is insoluble All A, B, and C four solutions, it belongs to

  1. Carboxylic acids
  2. Amines
  3. Inert class of hydrocarbons
  4. Neutral class

Question’s Answer: Inert class of hydrocarbons


Which of the mentioned class of compound gives a positive NaHCO3 test?

  1. Inert class of hydrocarbons
  2. Carboxylic acids
  3. Amines
  4. Neutral class

Question’s Answer: Carboxylic acids


__________ class of compound gives a positive neutral FeCl3 test.

  1. Phenols
  2. Amines
  3. Carboxylic acids
  4. Inert class of hydrocarbons

Question’s Answer: Phenols


_________ class of compound gives a positive diazotization test.

  1. Inert class of hydrocarbons
  2. Carboxylic acids
  3. Amines
  4. Phenols

Question’s Answer: Amines


_____ class of compound gives Molisch test.

  1. Phenols
  2. Amines
  3. Carboxylic acids
  4. Carbohydrates

Question’s Answer: Carbohydrates


_____ class of compound gives 2,4 DNP test.

  1. Carbonyl compounds
  2. Carbohydrates
  3. Carboxylic acids
  4. Phenols

Question’s Answer: Carbonyl compounds


_____ class of compound gives soda lime test.

  1. Carbonyl compounds
  2. Amides & anilines
  3. Carboxylic acids
  4. Phenols

Question’s Answer: Amides & anilines


Which of the mentioned class of compound gives silver mirror test?

  1. Aldehydes
  2. Amides & anilines
  3. Carboxylic acids
  4. Phenols

Question’s Answer: Aldehydes


_____ class s of compound gives iodoform test.

  1. Amides & anilines
  2. Aldehydes
  3. Phenols
  4. Ketones

Question’s Answer: Ketones


____________test is helpful and used to distinguish between primary, secondary and tertiary alcohols.

  1. Lucas test
  2. Molisch test
  3. Soda lime test
  4. Bromine test

Question’s Answer: Lucas test


Fehling solution test is given by

  1. Fructose
  2. Glucose
  3. Both A & B
  4. Starch

Question’s Answer: Both A & B


More Organic chemistry MCQs

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