ECAT Pre Engineering Chemistry Chapter 19 MCQ Test With Answer

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

Alkenes combine readily with electrophillic reagents such as halogens giving

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

Hydrocarbons contain :

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

Alkanes containing carbon C₁₈ownwards are

• Gases A
• Liquids B
• Waxy solids C
• Solids D

The electron releasing effect of methyl group is significant and it makes ring a good

• Electrophilic A
• Nucleophilic B
• Nucleophobic C
• Hydrophobic D

Hydrocarbon which is liquid at room temperature is

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

Hybridization in alkanes is:

• sp A
• sp² B
• sp³ C
• dsp² D

The order of dehydration of alcohol

• 10> 20> 30 A
• 10> 30> 20 B
• 20> 30> 10 C
• 30> 20> 10 D

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

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

During nitration of benzene, the active nitrating agent is

• NO3 A
• NO2+ B
• NO2- C
• HNO3 D

Vinyl acetylene combines with HCI to form

• Poly acetylene A
• Benzene B
• Chloroprene C
• Divinylacetylene D

Alkenes normally have ______ geometry

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

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

Odour of alkene is:

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

The four bonds of carbon in methane are directed towards the corners of

• Cube A
• Pentagon B
• Hexagon C
• Tetrahedron D

Aromatic hydrocarbons are the derivatives of

• Normal series of paraffins A
• Alkene B
• Benzene C
• Cyclohexane D

When acetylene is passed through a copper tube at 300°C, it polymerizes to

• Polyacetylene A
• polyethylene B
• Benzene C
• None of these D

Boiling point of n-butane is:

• -102°C A
• -75°C B
• -55°C C
• 55°C D

The alkynides are used for the ----------- of alkynes

• Pxperation A
• Purification B
• Seperation C
• All of above D

When n-hexane is heated in the presence of Pt at 500°C, it cyclists to give

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

Preparation of vegetable ghee involves

• Halogenations A
• Hydrogenations B
• Hydroxylation C
• Dehydrogenations D

Hybridization of each carbon atom in benzene ring is

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

Which one does not declourized KMnO₄

• Alkenes A
• Alkynes B
• Bezene C
• All above D

For preparing an alkane, a concentrated aqueous solution of sodium or potassium salt of saturated carboxylic acid is subjected to

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

Acetylene when treated with 10% H₂SO₄in the presence of HgSO₄adds one molecule of water to form

• Aldehydes A
• Esters B
• Alcohols C
• Acids D

A single benzene ring can have ______ ortho position maximally

• One A
• Two B
• Three C
• Four D

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

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

The reaction in which ketone is reduced to the alkane is called

• Kolb A
• Clemmensen B
• Cannizzaro C
• None D