ECAT Pre Engineering Chemistry Chapter 19 MCQ Test With Answer

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

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

The sp²hybird orbitals are oriented in space at one angle

• 180° A
• 109.5° B
• 100° C
• 120° D

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

Which can be used for dehydration of alcohol

• P₄O₁₀ A
• H₂SO₄ B
• H₃PO₄ C
• All of them D

The electrophile in aromatic sulphonation is

• H₂SO₄ A
• HSO₄ B
• SO₃ C
• SO₃⁺ D

Free radical mechanism of halogenation of alkanes follow step:

• Initiation A
• Propagation B
• Termination C
• All of these D

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

• Ethene A
• Ethane B
• Methane C
• Propane 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

The simplest and the parent members of aromatic hydrocarbon is

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

The correct order of reactivity of halogens with alkanes is

• l₂> Br₂> Cl₂> F₂ A
• l₂> Cl₂> F₂> Br₂ B
• F₂> Cl₂> l₂> Br₂ C
• F₂> Cl₂> Br₂> l₂ 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

Cyclohexane can be converted not benzene in the presence of

• Pt at 100°C A
• Pt at 250°C B
• Pd at room temperature C
• Pt at room temperature D

B-B'-dichloroethyl sulphide is commonly known as

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

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

• Saturation A
• Unsaturation B
• Subsitution C
• None D

Acetylene gives

• White ppt. with ammonical AgNO3 and red ppt. with ammonical Cu(NO3)2 A
• White ppt. with ammonical AgNO3 and red ppt. with ammonical Cu2C12 B
• White ppt. with both C
• Red ppt. with both D

Hybridization in alkanes is:

• sp A
• sp² B
• sp³ C
• dsp² 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

Benzene does not undergo

• Substitution reaction A
• Addition reaction B
• Oxidation reaction C
• Elimination reaction D

Amongst the following the compound that can be most readily sulphonated is

• Toluene A
• Benzene B
• Nitrobenzene C
• Chlorobenzene D

Catalytic oxidation of alkanes is used for the preparation of

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

Sulphuric acid generates nitronium ion by reacting with

• Nitric acid A
• Nitrogen gas B
• Nitrous acid C
• Potassium nitrate D

Sp³hybird orbitals are oriented at an angle of

• 107.5° A
• 108.5° B
• 109.5° C
• 103.5° D

Which of the following is not aromatic hydrogencarbon

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

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

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

Synthesis rubber is made by polymerization :

• Chloroform A
• Acetylene B
• Divinyl acetylene C
• Butene D

Which is liquid among the following alkenes?

• Ethane A
• Propene B
• Butene C
• Pentene D

• 4-methyl pentene A
• 2-methyle-1-butene B
• 2-methyl propane C
• None of the above D

The reaction-method that does not give an alkane is

• Catalytic hydrogenation of alkanes A
• Wurtz reaction B
• Hydrolysis of alkyl magnesium bromide C
• Dehydrohalogenation of an alkyl halide D