ECAT Pre Engineering Chemistry Chapter 19 MCQ Test With Answer

Which reaction sequence would be best to prepare 3-chloro-aniline from benzene?

• Chlorination, nitration, reducing A
• Nitration, chlorination, reducition B
• Nitration, reduction,chlorination C
• Nitration, reduction, acylation, chlorination, hydrolysis D

Marsh gas was the name given to

• Methane A
• Ethane B
• Propane C
• Butane D

Odour of alkene is:

• Fruity A
• Odourless B
• Zarlic like C
• Irritating D

The molecule of ethane possess which hybrization

• sp³ A
• sp² B
• sp C
• sp²d D

Benzene is prepared from n-hexane in the presence of catalyst

• Cr₂O₃ A
• Al₂O₃ B
• SiO₂ C
• All above D

• 2-bromonitrobenzene A
• 2-nitrobromobenzene B
• 1-bromonitrobenzene C
• 1-nitrobromobenzene D

The three alternate single and double bonds in the benzene ring are called

• Conjugate bonds A
• Resonating bonds B
• Both A and B C
• None of above D

Hybridization of each carbon atom in benzene ring is

• sp hybridized A
• sp²hybridized B
• sp³ C
• dsp² D

Alkyne is :

• CH_3-CH₃ A
• CH₄ B
• CH₂₌CH₂ C
• C₂H₂ D

Which of the following reaction is characteristic of benzene

• Electrophilic substitution reaction A
• Reduction B
• Oxidation C
• Ozonolysis D

Write the name of following alkene CH₂= CH - CH = CH₂

• 1,3 butadiene A
• Butra -1, 3-diene B
• Both a & b C
• None D

Alkanes are soluble in all except

• Benzene A
• Ether B
• Water C
• Carbon tetra chloride D

The treatment of benzene with isobutene in the presence of sulphuric acid give

• isobutyl benzene A
• tert-Butyl benzene B
• n- Butyl benzene C
• no reaction D

Which one gives acidic reactions?

• CH₃----C≡C-------CH₃ A
• CH₃-----CH₂-----HC=CH----CH₂ B
• CH₃----CH=CH₂ C
• CH₃-----C≡CH D

Preparation of ethylbenzene by the reaction of bromobenzene, ethylbromide and sodium is called

• Wurtz reaction A
• Fitting reaction B
• Wurtz fitting reaction C
• None of these D

An alkynes having Carbon count of 20 is

• gas A
• liquid B
• Solid C
• None D

When methane reacts with Cl₂in the presence of diffused light the products obtained are?

• Chloroform only A
• Carbon tetrachloride only B
• Chloromethane and dichloromethane C
• Mixture of a,b,c D

The hydrocarbon used for polymerization is

• Alkanes A
• Alkenes B
• Alkynes C
• All of above D

The method in which alkanes prepared by alkyle halides in the presence of palladium - charcoal is

• Hydrolysis A
• Electrolysis B
• Hydrogenation C
• Hydrogenolysis D

Which decolourizes the colour of Br₃

• CH₄ A
• CH_3-CH_3-CH₃ B
• CH₂₌CH₂ C
• CH_3-CH₃ D

When methane reacts with Cl₂in the presence of diffused light the products obtained are

• Chloroform only A
• Carbon tetrachloride only B
• Chloromethane and dichloromethane C
• Mixture of a, b, c D

Catalytic oxidation of alkanes is used for the preparation of

• Adehydes A
• Ketones B
• Fatty acid C
• Carbonyylic acids D

Which is symmetric alkene?

• CH=C-CH₂ A
• CH≡CH B
• CH₃-C≡C - CH₃ C
• B and C D

Formula of chloroform is:

• CH₃Cl A
• CCl₄ B
• CH₂Cl₂ C
• CHCl₃ D

The addition of unsymmetrical reagent to an unsymmetrical alkene is in accordance with the rule

• Hund's rule A
• Markowvikov's rule B
• Pauli's exclusion principle C
• Auf ban principle D

Which of the following is not an electrophitic substitution reaction of benzene

• Nitration A
• Sulphonation B
• Fridel-Craft alkylation C
• Free radical chlorination of benzene D

Octane number can be changed by

• Isomerisation A
• Alkylation B
• Cyclisation C
• All of these D

B-B'-dichloroethyl sulphide is commonly known as

• Mustard gas A
• Laughing gas B
• Phosgene gas C
• Bio gas D

Physical properties of alkanes increase with increase of all physical constants except

• Boiling points A
• Melting points B
• Density C
• Solubility D

Benzene has a -------- structure

• Pentagonal A
• Hexagonal B
• Heptagonal C
• Tetragonal D