ECAT Pre Engineering MCQ Test With Answer for Chemistry Full Book

Enzymes are chemically

• Carbohydrates A
• Proteins B
• Fatty acids C
• Phospholipids D

Which teat is not given by both glucose and fructose

• Give yellow ppt of CHl₃with alkaline aqueous iodine A
• With 2, 4-DNPH give yellow ppt of hydrazone B
• Evolve H₂gas with Na metal C
• Oxidised with [Ag(NH₃)₂]⁺i.e. Tollen's reagent 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 statement that the properties of every eight elements are similar to the first is the law of

• Dobereiner A
• Newland B
• Mendeleev C
• L. Meyer D

An organic compound has the following properties ; It gives a positive tri-iodomethane test; it gives a yellow ppt, with 2, 4-DNP regent; it does not react with Tollen's reagent . Which compound would give these results

• CH₃CHO A
• CH₃CH₂OH B
• CH₃CH₂COCH₃ C
• CH₃CH₂CH₂CHO D

A phtotographic plate is coated with an emulsion of silver nitrate and

• AgCI A
• AgI B
• AgBr C
• NaNO₃ D

The radius of first orbit of hydrogen atom

• 0.329 A° A
• 0.429 A° B
• 0.529 A° C
• 0.229 A° D

Phenol is used in the preparation of

• Bakelite A
• Phenatherene B
• Cellulose C
• All of these D

C₆H₁₂O₆ is molecualr formula of:

• Glucose A
• Dextrose B
• Fructose C
• All of these D

In endothermic reactions, the heat content of the:

• Products is more than that of reactants. A
• Reactants is more than than to products. B
• Both (a) and (b). C
• Reactants and products are equal. 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

When a metal is dipped in 1 molar of its solution at 298 K. then potential set up is called

• Standard electrode potential A
• Electric charge B
• Ionization potential C
• Electroplating D

Which compound of noble gas xenon can be prepared?

• Oxides A
• Fluoride B
• Oxyfluorides C
• All of these D

Which one of the following compounds does not have the empirical formula CH₂O?

• Ethanoic acid, CH₃CO₂H A
• Ethanol, CH₃CH₂OH B
• Glucose, C₆H₁₂O₆ C
• Methanal, HCHO D

NO and NO₂gases in atmosphere are represented by

• NO A
• NO₄ B
• NO_x C
• N_xO_y D

In 1903 Arthur Lapeworth became the first chemist to investigate a reaction mechanism. The reaction he investigated was that of hydrogen cyanide with propanone. What do we now call the mechanism of this reaction

• Electrophilic addition A
• Electrophilic substitution B
• Nucleophilic addition C
• Nucleophilic substitution D

The conversion of n-hexane into benzene by heating in the presence of CO, is called

• lsomerization A
• Aromatization B
• Dealkylation C
• Rearrangement 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 amount of oxygen in the lithosphere is about

• 35.50% A
• 40.60% B
• 56.60% C
• 50.50% D

Which reaction yields Bakelite?

• Urea with HCHO A
• Tetramethyl glycol with Hezamethylene diisocyanate B
• Phenol and HCHO C
• Ethylene glycol and Dimethylterephthalate D

Benzene is an example of

• Aromatic compound A
• Cyclic compound B
• Aliphatic compound C
• A cyclic compound D

Metals like Fe, Mg, Al, Cr, Zn have more negative reduction potentials that is whey

• These don't react with steam A
• These react very slowly with steam to liberate H₂gas B
• These react rapidly with steam to produce the metallic oxides and liberate H₂gas C
• These react with cold water violently D

It is noticed that energy in the form of heat is either evolved or absorbed as a result of a

• Physical change A
• Chemical change B
• Biological change C
• All of above D

When quantity of electricity passed is one faraday then the mass deposited at the electrode is equal to

• One gm, atomic weight A
• One gm, Equivalent B
• Eletrochemical equivalent C
• None of the above D

Which of the following waste material is not recycled for use again

• Paper A
• Plastic B
• Hides of animals C
• Glass D

Prevention of corrosion of iron by Zn coating is called

• Galvanization A
• Cathodic protection B
• Electrolysis C
• Photoelectrolysis D

Which one of the following has no units of its K_cvalue

• 
  A
• 
  B
• 
  C
• 
  D

Which of the following is a water soluble vetamin?

• Niacin A
• Riboflavin B
• Trypsin C
• Ascorbic acid D

Which of the following with aqueous KOH will give acetaldehyde?

• 1, 2-Dichloroethane A
• 1,1-Dichloroethane B
• Chloracetic acid C
• Ethyl chloride D

• It decolourises aqueous bromine rapidly A
• It is insoluble in water B
• It reduces Fehling's reagent C
• Two molecules react with each other in the presence of a strong acid D