ECAT Pre Engineering Chemistry Chapter 19 MCQ Test With Answer

Octane number is zero for

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

Replacement of hydrogen by NO₂group is called

• Sulphonatioin A
• Hydration B
• Nitration C
• Cracking D

Which decolourizes the colour of Br₃

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

Octane number can be changed by

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

The C-C bond angles in benzene ring are

• 119° A
• 120° B
• 121° C
• None 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

An alkane is produced when an alkyle halide reacts with zinc in the presence of

• HCl A
• CH₃COOH B
• Both a & b C
• None D

In CH₄, all the H-C-H bond angles are

• 120° A
• 107° B
• 109° C
• 109.5° D

Alkenes combine readily with electrophillic reagents such as halogens giving

• Haloalkanes A
• Gem-dihalides B
• Vicinal dihalides C
• Vinyl halides D

The addition of HBr is easiest with

• CH2 = CHCl A
• CICH = CHCl B
• CH3 - CH = CH2 C
• (CH3)2 C = CH2 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

When alkyl is treated with chlorine in the presence of sunlight

• 1,3 dichloroproduct is formed A
• 1,4 dichloro product is formed B
• 1,3,5 trichloro product is formed C
• Only alkyl group is substituted D

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

• 2 A
• 1 B
• 3 C
• 4 D

The simplest and the parent members of aromatic hydrocarbon is

• Benzene A
• Toluene B
• Biphenyis C
• Naphthalene D

In which one of the following compound rings are not fused together at ortho positions

• Phenanthrene A
• Naphthalene B
• Diphenyemethane C
• Anthracene D

During nitration of benzene, the active nitrating agent is

• NO3 A
• NO2+ B
• NO2- C
• HNO3 D

The hydrocarbon which is used as an illuminating agent

• Methane A
• Methene B
• Methyne C
• B & C D

Which of the following method is most appropriate for the manufacture of methane?

• By reduction of CH2CL2 A
• Wurtz reaction B
• Liquification of natural gas C
• None of these D

Benzene was discovered by Michael Faraday's in

• 1824 A
• 1825 B
• 1826 C
• 1827 D

The presence of a double bond in a compound is the sign of

• Saturation A
• Unsaturation B
• Substitution C
• None of above D

Alkanes are generally not reactive towards acids, alkalis, oxidation or reuducing agents. They however undergo some reactions, which one is the reaction undergone by alkanes

• Elemination A
• Addition B
• Free radical substitution C
• Nucleophilic substation D

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

Acetylene is used in the manufacture of

• Rubber A
• Plastic B
• Ethyle alcohol C
• All of these D

Which of the following reaction is characteristic of benzene

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

The Total coal resources of Pakistan are estimated to be

• 184 billion A
• 184 million tones B
• 1.84 billion tounes C
• 1.84 million tonnes D

Which one of the following gases is used for artificial ripening of fruits

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

Which of the following is an ortho-para directing group

• 
  A
• 
  B
• 
  C
• 
  D

Complete combustion of alkane yields

• CO₂+ H₂O A
• CO₂+ heat B
• CO + H₂O heat C
• CO₂+ H₂O + heat D

Synthetic rubber is made by polymerization of

• Chloroform A
• Acetylene B
• Divinlacetylene C
• Butene D

Mustard gas is a :

• Gas A
• Liquid B
• Solid C
• High boiling point D