ECAT Pre Engineering Chemistry Chapter 19 MCQ Test With Answer

The process in which orbitals of different energies and shapes mix with each other to give equivalent hybrid orbitals is called

• Isomerization A
• polymerization B
• Hybridization C
• Resonance D

Incomplete oxidation of alkanes yields

• CO₂& carbon black A
• CO₂+ heat B
• CO and carbon black C
• CO + heat D

During the preparation of alkynes the active metals that react with tetra halo-alkanes are

• Zn A
• Mg B
• Both a and b C
• None D

Paraffins are also called

• Alkanes A
• Alkynes B
• Alkenes C
• None of these D

How many isomeric disubtituted products are obtained by the introducing of second group in the ring

• Two A
• Three B
• Four C
• None D

Kolb's method is not useful for the production of

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

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

• Hund's rule A
• Markownikov's rule B
• Pauli's Exclusion principle C
• Auf ban principle D

Alkyl benzenes are readily oxidized by axidfied

• KMnO₄ A
• K₂CO₃ B
• MnO₄ C
• H₂SO₄ D

Benzene is obtained from benzene sulphonic acid by treating with

• HCl A
• NaOH B
• H₂O C
• NaHCO₃ D

Polymerization of ethane take place at pressure of 100 atm and a temperature of

• 200°C A
• 400°C B
• 600°C C
• 800°C D

Which of the following species participate in sulphonation of benzene ring?

• H2SO4 A
• HSO4 B
• SO3 C
• SO^-₂ D

Benzene can be obtained by heating either benzoic acid with X or phenol with Y. X and Y are respectively

• Zinc dust and soda lime A
• Soda time and zinc dust B
• Zinc dust and sodium hydroxide C
• Soda lime and copper D

Octane number is zero for

• n-Heptane A
• Isooctane B
• n-Hexane C
• Isoheptane D

An alkynes having Carbon count of 20 is

• gas A
• liquid B
• Solid C
• None D

Introduction of a second methyl group in methylbenzene will give how many isomeric dimethyllenzenes

• 2 A
• 1 B
• 3 C
• 4 D

Which decolourizes the colour of Br₃

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

Alkenes normally have ______ geometry

• Tetrachedral A
• Linear B
• Planer C
• None D

Nitroalkane are used in

• Fuel A
• Solvents B
• Organic synthesis C
• All of them D

CnH_2nis the general formula of

• Alkanes A
• Alkanes B
• alkynes C
• None of above D

Octane number can be changed by

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

Ethylene polymerizes at 100 atm pressure and 400°C to give

• Polybenzene A
• Polyalcohol B
• Polypropylene C
• Polyethylene D

• Pent -1-ene-3-yne A
• 2-pentyne-4-ene B
• 1-pentene-3-yne C
• Pent-2-yen-4-ene D

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

• Hund's rule A
• Markownikov's rule B
• Pauli's Exclusion Principle C
• Auf bau Principle D

Which one of the following is (m-xylene)

• 1,2 dimethyl benzene A
• 1,3 dimethyl benzene B
• 1,5 dimethyl benzene C
• 1,4 dimethyl benzene D

Hydrocarbons contain :

• Carbon only carbon A
• Hydrogen only B
• Carbon & hydrogen C
• Carbon , hydrogen & halogen D

Alkene general formula :

• C_nH_2n+2 A
• C_nH_2n B
• C_nH_2n-2 C
• C_nH_2n+1 D

The order of reactivity of halogens in aliphatic substitution reactions is

• Br2 > C12 > F2 A
• C12 > Br2 > F2 B
• C12 C12 > Br2 C
• F2 > Br2 > C12 D

Which reaction is too vigorous to control

• Chlorination A
• Bromination B
• Iodination C
• Fluorination D

Alkyl halides when reduced with nascent hydrogen in the presence of Zn + HCI, are converted to

• Alkynes A
• Alkenes B
• Alkanes C
• Alcohol D

• 2, 3-dimethylbutane A
• 2, 3-methylbutane B
• 2-dimethylbutane C
• Dimethylbutane D