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Q1. Separation of mixture into a thin layer of adsorbent is known as:

• Column Chromatography
• Adsorption chromatography
• Partition chromatography
• Thin layer chromatography

Solution

Separation of mixture into a thin layer  of adsorbent is known as Thin layer Chromatography.

Q2. Which one of the following IUPAC name is incorrect?

• Ethanoic acid
• Pent - 3 - ene
• Ethanal
• 3-methyl pentan- 2-ol

Solution

The numbering of double bond is 2 from the other end of the chain. The numbering is done to give the lowest possible no. to the double bond.

Q3. Which of the following species is not an electrophile?

• AlBr₃
• BF₃
• SnCl₄
• NH₃

Solution

Electrophiles are those which have tendency to accept electrons.Ammonia has an unshared pair of electrons and thus is a lewis base.

Q4. Halogenation proceeds via:

• Free radical chain mechanism
• Termination
• Combustion
• Addition process

Solution

Halogenation proceeds via free radical chain mechanism.

Q5. Laissaigne's extract is made to:

• Convert ionic compounds to covalent compounds
• Convert covalent compounds to ionic compounds
• Dissolve the compound
• None of these

Solution

Laissaigne's extract is made to convert covalent compounds to ionic compounds.

Q6. C₃H₆O represents an aldehyde and a ketone is a type of:

• Functional group isomerism
• Position isomerism
• Chain isomerism
• Metamerism

Solution

C₃H₆O represents an aldehyde and a ketone is a type of  functional group isomerism.

Q7. Majority of the reactions of alkynes are the examples of:

• Displacement reactions
• Addition reaction
• Homolytic cleavage
• Optical isomerism

Solution

Majority of the reactions of alkynes are the examples of Addition reaction.

Q8. Estimation of nitrogen is done by:

• Potentiometric method
• Dubas method
• Kjeldahls method
• Carius method

Solution

Estimation of nitrogen is done by Kjeldahls method.    

Q9. Addition of dihydrogen to propyne forms:

• Ethanal
• Propene
• carbanion
• Carbocation

Solution

Addition of dihydrogen to propyne forms propene .

Q10. Pentane , isopentane and neopentane is a type of:

• Position isomerism
• Geometrical isomerism
• Chain isomerism
• Optical isomerism

Solution

Pentane , isopentane and neopentane is a type of chain isomerism.

Q11. Which among the following is a very unstable and reactive species:

• Polar ions
• Free radical
• Carbaanion
• Carbocation

Solution

Carbocation is a very unstable and reactive species. 

Q12. Reagent that takes away an electron pair is called as:

• Carbocation
• Carbanion
• Electrophile
• Nucleophile

Solution

Reagent that takes away an electron pair is called as Electrophile.

Q13. C₃H₈O represents two alcohols - Propan-1-ol  and Propan-2-ol is a type of:

• Position isomerism
• Functional group isomerism
• Geometrical isomerism
• Optical isomerism

Solution

C₃H₈O represents two alcohols - Propan-1-ol  and Propan-2-ol is a type of Position isomerism.

Q14. A reagent that brings an electron pair is known as:

• Nucleophile
• Electrophile
• Inductivity
• Conjugation

Solution

A reagent that brings an electron pair is known as nucleophile.  

Q15. A pale yellow precipitate soluble in ammonium hydroxide solution indicates the presence of:                 

• Bromine
• chlorine
• Phosphorus
• Iodine

Solution

A pale yellow precipitate soluble in ammonium Hydroxide solution indicates the presence of Bromine.

Q16. Alkyl groups directly attached to the positively charged carbon stabilize the carbocations due to:

• Isomerism
• Chirality
• Inductive and hyperconjugation effect
• Resonance effect

Solution

Alkyl groups directly attached to the positively charged carbon stabilize the carbocations due to inductive and hyperconjugation effect.

Q17. C₅H₁₂ represents three compounds and are types of:

• Optical isomerism
• Chain isomerism
• Geometrical isomerism
• Position isomerism

Solution

C₅H₁₂ represents three compounds that are types of  chain isomerism.

Q18. Process of separation of mixtures into their components and to purify the compounds by using adsorption is known as:

• Differential extraction
• Chromatography
• Sublimation
• Distillation

Solution

Process of separation of mixtures into their components and to purify the compounds is known as chromatography.

Q19. Which of the following compounds will exhibit geometrical isomerism?    

• 1 - Phenyl - 2 – butene
• 3 - Phenyl - 1 – butene
• 2 - Phenyl - 1 – butene
• 1, 1 - Diphenyl - 1 propane  

Solution

An organic compound will exhibit geometric isomerism only when each of its double bonded carbon is bonded to two different groups.    

Q20. A sequential account of each step, describing details of electron movement, energetics during bond cleavage and bond formation, and the rates of transformation of reactants into products (kinetics) is referred to as:

• Reaction kinetics
• Reaction mechanism
• Thermodynamics
• Equation

Solution

A sequential account of each step, describing details of electron movement, energetics during bond cleavage and bond formation, and the rates of transformation of reactants into products (kinetics) is referred to as reaction mechanism.

Q21. Write the IUPAC name of the compound COOH-C=C-COOH.

• But-2-ene-1,4-dioic acid
• But-2-ene-1,2-dioic acid
• But-1-ene-1,4-dioic acid
• Bromo-4-chlorobutane

Solution

The IUPAC name of the compound  COOH-C=C-COOH  is But-2-ene-1,4-dioic acid.

Q22. The white precipitate which is formed in the detection of chloride ion is due to the formation of:

• Ammonium chloride
• Sodium chloride
• Calcium chloride
• Aluminium sulphate

Solution

This white precipitate which is formed in the detection of chloride ion is due to the formation of Ammonium chloride.

Q23. CH₃Cl gives CH₃⁺ + Cl^- is a:

• Linear cleavage
• Homolytic cleavage
• Heterolytic Cleavage
• None of these

Solution

As after cleavage one of the atom has sextet electronic configuration and the positive charge whereas the other atom has at least one lone pair and the negative charge . Hence it is a Heterolytic Cleavage.

Q24. How are essential oils purified?

• By evaporation
• By condensation
• By chromatography
• By steam distillation

Solution

Steam distillation is used to separate organic compounds that tend to decompose at high temperature. Essential oils can be purified by steam distillation.

Q25. Organic compounds are broadly classified as:

• Acyclic and cyclic compounds
• Benzenoid compounds
• Open chain compounds
• Closed chain compounds

Solution

Organic compounds are broadly classified as acyclic and cyclic compounds.    

Q26. The oganic reaction which proceeds through heterolytic bond cleavage are known as:

• Free radical reaction
• Ionic reactions
• Covalent reactions
• Polar reactions

Solution

The oganic reaction which proceeds through heterolytic bond cleavage are known as Ionic reactions.

Q27. One molecule of water adds to alkynes on warming with mercuric sulphate and dilute sulphuric acid to form:

• Carbonyl compound
• Propane
• Isopropyl free radical
• Ethyl free radical

Solution

One molecule of water adds to alkynes on warming with mercuric sulphate and dilute sulphuric acid to form  Carbonyl compound.

Q28. Benzene and toluene can be separated by:

• Simple distillation
• Fractional distillation
• Filtration
• Evaporation

Solution

  Benzene and toluene can be separated by Simple distillation as the boiling difference is more.

Q29. In Carius method of estimation of halogens, 250 mg of an organic compound gave 141 mg of AgBr. The percentage of bromine in the compound is (At. Mass Ag = 108; Br = 80)

• 24
• 36
• 48
• 60

Solution

Q30. When there is breaking of bonds in such a way that the shared pair of electrons remains with one of the fragments it is termed as:

• Geometrical isomerism
• Heterolytic cleavage
• Homolytic cleavage
• Metamerism

Solution

When there is breaking of bonds in such a way that the shared pair of electrons remains with one of the fragments it is termed as Heterolytic cleavage.

Q31. Tetrahydrofuran is a type of:

• p-block elements
• Closed chain organic compound
• Open chain organic compound
• Inorganic compound

Solution

Tetrahydrofuran is a type of closed chain organic compound.

Q32. Detection of nitrogen, sulphur, halogens and phosphorus in an organic compound is done by:

• Victor-meyer test
• Lassaignes test
• Dumas method
• Metal-carbon test

Solution

Detection of nitrogen, sulphur, halogens and phosphorus in an organic compound is done by Lassaignes test.                        

Q33. Which of the following free radical is the most stable :

• Methyl
• Primary
• Secondary
• Tertiary

Solution

Larger is the no. of alkyl groups attached to the carbon atom, more stable is the free radical as more hyperconjugating structures are formed.

Q34. The number of secondary carbon atom in (CH₃)₂CHCH₂CH(CH₃)₂ is:

• 1
• 2
• 3
• 4

Solution

The carbon which is attached to two other  carbon atoms is secondary carbon atom.

Q35. Which one of the following species has electron releasing effect?

• -CHO
• –NO₂
• –CH₃
• –COOH

Solution

–CH₃ is an electron releasing group due to hyperconjugation.

Q36. Write the IUPAC name of the compound  CH₃CH=CH-CH₂Br.

• 1-ene- bromobutane
• 1 bromobutane
• 1 bromobutyne
• 1 bromo--but- 2-ene

Solution

The IUPAC name of the compound  CH₃CH=CH-CH₂Br is 1-bromo-but-2-ene.

Q37. To separate different fractions in petroleum industry we employ:

• Differential extraction
• Fractional Distillation
• Steam distillation
• Paper chromatography

Solution

To separate different fractions in petroleum industry we employ Fractional distillation.

Q38. When sodium fusion extract is acidified with nitric acid followed by silver nitrate, a white precipitate soluble in ammonium hydroxide show the presence of:

• Iodine
• Chlorine
• Bromine
• Fluorine

Solution

When sodium fusion extract is acidified with nitric acid followed by silver nitrate, a white precipitate soluble in ammonium hydroxide show the presence of chlorine.                                                      

Q39. The number of isomers possible for a disubstituted benzene are:

• One
• Two
• Three
• four

Solution

For a  disubstituted benzene, the isomers possible are ortho, meta and para.

Q40. Paper chromatography is a type of:

• Column chromatography
• Partition chromatography
• Adsorption chromatography
• Thin layer chromatography