ECAT Pre Engineering MCQ Test With Answer for Chemistry Full Book

Among the following, poly cyclic compound is

• styrene A
• cumene B
• naphthalene C
• xylene 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

Ethyl acetate reacts with CH₃MgBr to form

• Secondary alcohol A
• Tertiary alcohol B
• Primary alcohol and acid C
• Acid D

The value of SHE is cathode and anode is always taken to be

• One A
• Zero B
• Different C
• Same D

Matals usually conduct electricity because

• There are mobile electrons in the metallic structure A
• Metals are decomposed by current B
• Metals have high resistance C
• In metals the ions are free to move D

The range of visible spectrum is

• 300 - 600 nm A
• 600 - 900 nm B
• 400 - 750 nm C
• 100 - 300 nm D

The reaction between fat and NaOH is called

• Esterification A
• Hydrogenolysis B
• Fermentation C
• Saponification D

The valence orbital configuration of an element with atomic number 23 is

• 3d⁵ A
• 3d³, 4s² B
• 3d³, 4s¹, 4p¹ C
• 3d²,4s²,4p¹ D

The solubility of PbF₂is 2.6 x 10^-3mole dm^-3 then its solubility product is

• 2.6 x 10^-3 A
• 6.76 x 10^-6 B
• 5.2 x 10^-6 C
• 7.0 x 10^-8 D

Photons of yellow colour are ______ energetic than violet colour

• More A
• Less B
• Equal C
• None D

During electrolysis of KNO₃, H₂is evolved

• Anode A
• Cathode B
• Both a and b C
• None D

Orbitals having same energy are called

• Hybrid orbitals A
• Valence orbitals B
• Degenerate orbitals C
• D-orbitals D

Which of the following expressions show a heterolytic bond fission

• 
  A
• 
  B
• 
  C
• 
  D

In a chemical change, the energy in the form of heat will either be evolved or absorbed and this is called

• Endothermic A
• Heat of products B
• Exothermic reaction C
• Heat of reaction D

Which acid is used in the manufacture of synthetic fibre?

• Formic acid A
• Oxalic acid B
• Carbonic acid C
• Acetic acid D

• 3 A
• 4 B
• 5 C
• 2 D

Iodoform test is given by:

• Formaldehyde and Higher ketones A
• Formaldehyde B
• Acetaldehyde and methyl ketones C
• Acetaldehyde D

Angle 120° is observed in molecules :

• CH₄ A
• CH_3-CH₃ B
• CH -CH C
• CH_{2 =}CH₂ D

How should condition be changed to prevent the volume of a given gas from expanding whine its mass is increased ?

• Temperature is lowered and pressure is increased A
• Temperature is increasedand pressure is lowered B
• Temperature and pressure both are lowered C
• Temperature and pressure both are increased D

Which of the following compounds does not react with NaHSO₃?

• C₆H₅CHO A
• Acetophenone B
• Acetone C
• Acetaldehyde D

The process in which orbitals of different energies and shapes mix with each other to give equivalent hybrid orbitals is called

• Isomerization A
• polymerization B
• Hybridization C
• Resonance D

Colour of chlorine is

• Pale yellow A
• Greenish yellow B
• Red brown C
• Greyish black D

The substance having highest conductivity at room temperature among the following is

• 0.1 N HCl A
• 0.1 N NaCl
  B
• Graphite C
• Glass D

During dehydration of alcohols to alkenes by heating with conc. H₂SO₄, the initial step is

• Formation of an ester A
• Protonation of alcohol molecule B
• Formation of carbocation C
• Elimination of water D

On the basis of VSEPR theory SO₂is a

• Liner molecule A
• A bent molecule B
• A strong molecule C
• A gaseous molecule D

The reaction of aromatic acyl chloride and phenol in the presence of a base NaOH or pyridine is called

• Kolbe's reaction A
• Perkin's reaction B
• Sandmeyer's reaction C
• Schotten Baumann reaction D

An ion bearing positive charge is called:

• Cation A
• Positron B
• Anion C
• None of above D

The unit of specific conductivity is

• Ohm cm^-1 A
• Ohm cm^-2 B
• Ohm^-1cm C
• Ohm^-1cm^-1 D

Scientific study of fermentation was first made by

• Buchner A
• Liebig B
• Biot C
• Pasteur D

In sp²hybridization bond angle is _____

• 120° A
• 180° B
• 109.5° C
• None D