ECAT Pre Engineering MCQ Test With Answer for Chemistry Full Book

The standard enthalpy change in the formation of 1 mole of a compound from its elements in their standard physical states is

• Enthalpy of formation A
• Enthalpy of atomization B
• Enthalpy of neutralization C
• Internal energy change D

Variable valency is characteristic of

• Halogen A
• Transition elements B
• Alkali metals C
• Noble gas D

Which of the following is a constituent of nylon?

• Adipic acid A
• Styrene B
• Teflon C
• None of these D

Which is the chain isomer of n-pentane

• Isopentane A
• Neopentene B
• N-pentene C
• Isopentene D

One mole of ethanol and one mole of ethane have an equal

• Mass A
• Number of atoms B
• Number of electrons C
• Number of molecules D

Aniline reacts with which of these to form Schiff base?

• Acetic acid A
• Bezaldehyde B
• Acetone C
• NH₃ D

Grignard's reagent on treatment with chloramine give

• Acetamide A
• Primary amice B
• Secondary amice C
• Urea D

In alkynes the bonds between carbon atoms are

• All sigma bonds A
• All pi(π) bonds B
• One is sigma and two areπ(pi) bonds C
• One isπ(pi) and two are sigma bonds D

Hydrogen bond is the strongest between the molecules of

• HF A
• HCl B
• HBr C
• HI D

After chlorination, the pulp is washed at:

• 20°C A
• 30°C B
• 40°C C
• 60°C D

In endothermic reactions, the heat content of the

• Products is more than that of reactants A
• Reactants is more than that of products B
• Both a and b C
• None of the above D

The number of spherical nodes in 3p orbitals are

• One A
• Three B
• Non C
• Two D

Which is a protein?

• Nylon A
• Rayon B
• Natural silk C
• Terylene D

Peat before conversion to bituminous coal is converted to

• Lignite A
• Anthracite B
• Asphalt C
• None D

• High temperature and low pressure A
• Low temperature and low pressure B
• Low temperature and high pressure C
• High temperature and high pressure D

The free spaces between the metal atoms and its crystal lattice are called

• Valance spaces A
• Empty spaces B
• Interstices C
• None D

Reductive ozonolysis of benzene produces

• Acetone A
• Maleic anhydride B
• Phthalic acid C
• Glyoxal D

Synthetic rubber is made by polymerization of

• Chloroform A
• Acetylene B
• Divinlacetylene C
• Butene D

Distillation of calcium salts of acetic acid and formic acids gives acetaldehyde. What compound would be obtained if only calcium salt of acetic acid is distilled

• Formaldehyde A
• Butyraldehyde B
• Propionaldehyde C
• Acetone D

Nitrogen is present in atmosphere

• 36% A
• 78% B
• 89% C
• 21% 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

Tetrabromoethane on treatment with alcoholic zinc gives

• Ethylbromide A
• Ethane B
• Ethene C
• Ethyne D

If half life period of a reaction is independent of the concentration of the reactants, then the reaction is

• Zero order A
• First order B
• Second order C
• Order is in fraction D

The temp. and pressure used for PVC polymerization is

• 10°C and 10 atm A
• 20°C and 20 atm B
• 52°C and 9 atm C
• 100°C and 10 atm D

Covalent compound s mostly exist in the form of:

• Protons

  A

• Atoms

  B
• Neutrons C

• Molecules

  D

Ground and surface waters are contaminated and become polluted due to the human activity. Which human activity will bot cause water pollution

• Live stock waste A
• Agricultural pesticides B
• Oil breaks and spills C
• All of the above D

The intermolecular forces in liquids are

• Negligible A
• Very weak B
• Very strong C
• Reasonably strong D

The tip of the funnel should touch the side of the beaker in order to avoid

• Splashing A
• Leakage B
• Mixing C
• Contamination D

Reaction of HNO, with very dilute Zinc and at low temperature gives

• H₂ A
• NO B
• NO₂ C
• NH₄ D

Colour of chlorine is

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