ECAT Pre Engineering Chemistry Chapter 19 MCQ Test With Answer

During nitration of benzene, the active nitrating agent is

• NO3 A
• NO2+ B
• NO2- C
• HNO3 D

In Friedal-Craft's alkylation besides AlCl3 the other reactants are

• C6H6 + NH3 A
• C6H6 + NH4 B
• C6H6 + CH3Cl C
• C6H6 + CH3COCl D

The temp. used for the hydrogenation of alkenes using Ni is

• 2000°C A
• 400°C B
• 200-- 300°C C
• 1000°C D

The method involved for electrolysis of Na or K salts of carboxylic acids

• Sabatier's sendrens reaction A
• Kolbe's method B
• Clemmensen C
• Wolf kishner reduction D

B-B'-dichloroethyl sulphide is commonly known as

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

Which one does not declourized KMnO₄

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

All C - H bond lengths of benzene ring is

• 1.07A° A
• 1.09A° B
• 1.08A° C
• None D

The nitration of benzene takes place when it is heated with a mixture of conc.HNO₃and conc. H₂SO₄at 50°C in ratio of

• 1 : 2 A
• 1 : 1 B
• 1 : 3 C
• 2 : 1 D

The simplest and the parent members of aromatic hydrocarbon is

• Benzene A
• Toluene B
• Biphenyis C
• Naphthalene 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

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

A six membered ring containing one double bond called

• Cyclohexene A
• Cyclohexane B
• Cyclohexadiene C
• None 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 class of compound is more reactive

• Alkane A
• Alkene B
• Alkyne C
• None D

Meta directing group decreased the ----------- of benzene ring

• Physical activity A
• Chemical reactivity B
• Density C
• None D

Marsh gas was the name given to

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

The stability of acromatic compounds decreases with ------- in the no. of its resonance structure

• Decrease A
• Increase B
• Remain constant C
• Partially decreases D

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

Alkanes containing carbon C₁₈ownwards are

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

The method used only for the production of symmetrical alkanes

• Kolb's method A
• Clemmenen B
• Cannizzaro C
• Wolf kishner D

Which of the following is an ortho-para directing group

• 
  A
• 
  B
• 
  C
• 
  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

Alkenes normally have ______ geometry

• Tetrachedral A
• Linear B
• Planer C
• None 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

Benzene is obtained from benzene sulphonic acid by treating with

• HCl A
• NaOH B
• H₂O C
• NaHCO₃ D

An organic compound, on treatment with Br2 in CC14 gives bromoderivative of an alkene. The compound will be

• CH3 - CH = Ch2 A
• CH3CH = CHCH3 B
• HC = CH C
• H2C = CH2 D

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

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

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

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

The compound prepared by a substitution reaction of benzene is

• Acetophenone A
• Glyoxal B
• Cyclohexame C
• Hexabromo cyclohexane D