ECAT Pre Engineering Chemistry Chapter 19 MCQ Test With Answer

Preparation of ethylbenzene by the reaction of bromobenzene, ethylbromide and sodium is called

• Wurtz reaction A
• Fitting reaction B
• Wurtz fitting reaction C
• None of these D

The empirical formula of benzene is determined by

• IR spectra A
• U.V B
• Elemental analysis C
• NMR spectra 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

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

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

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

An alkynes having Carbon count of 20 is

• gas A
• liquid B
• Solid C
• None D

The saturated hydrocarbons usually end with suffix ______

• Ane A
• Ene B
• Yne C
• Oic D

The term aromatic was derives from

• Greek word A
• Latin B
• Russian C
• English 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

The order of reactivity of halogen acids towards alkenes

• HCl > HBr > Hl A
• HBr > HCl > HI B
• HCl > HBr C
• HI > HBr > HCl D

The C-C bond angles in benzene ring are

• 119° A
• 120° B
• 121° C
• None D

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

• Pxperation A
• Purification B
• Seperation C
• All of above 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 hydrocarbon which is used as an illuminating agent

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

Benzene does not undergo

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

Eletronegativity difference in C-C bond in alkanes is:

• Zero A
• Double B
• Half C
• 4.0 D

De halogenatiion of tetrahalides happens in the presence of active metal like

• Zn A
• Mg B
• Both a and b C
• None of them 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

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

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

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

Hydrocarbon which is liquid at room temperature is

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

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

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

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

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

All C - H bond lengths of benzene ring is

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

Benzene is obtained by fractional distillation of

• Heavy oil A
• Anthracene oil B
• Middle oil C
• Light oil D

Vinyl acetylene combines with HCl to form:

• Polyacetylene A
• Benzene B
• Chloroprene C
• Divinyl acetylene D

Boiling point of n-butane is:

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

The general formula of alkane is

• C_nH_2n+2 A
• C_nH_n B
• C_nH_2n C
• C₂H_2n-1 D

Benzene was discovered by Michael Faraday's in

• 1824 A
• 1825 B
• 1826 C
• 1827 D