ECAT Pre Engineering MCQ Test With Answer for Chemistry Full Book

At present the number of cement factories is Pakistan are

• 20 A
• 22 B
• 25 C
• 30 D

The degree of polarity of molecule is known as its

• Dipole moment A
• Moment arm B
• Bond energy C
• Ionic character D

Le-chatlier's principle is applied on the reversible reaction in order to

• Determine the rate of reaction A
• Predict the direction of reaction B
• Determine the extent of reaction C
• Find best conditions for favorable shifting the position of equilibrium D

• Increase in concentration of 1 A
• Decrease in concentration of I₂ B
• Increase in temperature C
• Increase in total pressure D

Benzene has a -------- structure

• Pentagonal A
• Hexagonal B
• Heptagonal C
• Tetragonal D

Ammonium carbonate when heated to 200°C gives a mixture of NH₃and CO₂vapour with a density of 13.0. What is the degree of dissociation of ammonia carbonate?

• 3/2 A
• 1/2 B
• 2 C
• 1 D

The elimination of hydrogen halide from adjacent carbon atoms is called

• Dehydrogenation A
• Hydrogenation B
• Dehydrohalogenation C
• Hydrohalogenation D

In Bohr model of hydrogen atom the distance between adjacent orbits increases away from the nucleus, the energy difference between the orbits

• Increases A
• Decreases B
• Reaming same C
• Orbits coincide D

Calcium carbonates contains oxygen in it:

• 48% A
• 50% B
• 53% C
• 60% D

C₆H₁₂O₆and C₁₂H₂₂O₁₁ are:

• Mono-atomic molecules A
• Diatomic molecules B
• Poly-atomic molecules C

• Hetero atomic molecules

  D

When during electrolysis of a solution of AgNO₃, 9650 coulombs of charge pass through the electroplating bath, the mass of silver deposited on the cathode will be

• 1.08 g A
• 10.8 g B
• 21.6 g C
• 108 g D

Which gasoline is better?

• Of low boiling point A
• Of low molecular mass B
• Of high octane C
• All of these D

Halogens are called.

• salt former A
• Light bearing B
• copper forming C
• None of these D

Synthesis of rubber is made by polymerization of

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

Among O, C, F, Cl, Br, the correct order of increasing radii is

• F O C Cl Br A
• F C O Cl Br B
• F Cl Br O C C
• C O F Cl Br D

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

Ozone in most of the tropical regions acts as a pollutant and causes

• Damages to eyes A
• Aggravates asthma B
• Chest discomfort C
• All of these D

In the atmosphere, O₂is about

• 10% A
• 15% B
• 21% C
• 25% D

S_N1 reaction of alkylhalides leads to

• Retention of configuration A
• Recemisation B
• Inversion of configuration C
• None of these D

Which gas is used for welding purposes

• Butane A
• Nitrogen B
• Methane C
• Acetylene D

Mark the correct statement

• Na⁺ is smaller than Na atom A
• Na⁺is larger than Na atom B
• Cl^-is the smaller than Cl atom C
• Cl^-(ion) and Cl (atom) are equal in size D

Propanone is the product obtained by dehydrogenation of

• 2-Propanol A
• 1-Propanol B
• Isobutyl alcohol C
• Propanethoil D

The maximum number of electrons in a subshell for which l = 3 is

• 14 A
• 10 B
• 8 C
• 4 D

The iron obtained from blast furnace is

• Pig iron A
• Wrought ion B
• Soft ion C
• Steel D

The number of elements in the first, second and third period are

• 2, 8, 18 A
• 8, 2, 18 B
• 2, 18, 8 C
• 2, 8, 8 D

DDT is formed from

• Benzene and Chlorobenzene A
• Chloral and Chlorobenzene B
• Chloral and Benzene C
• Chlorobenzene and chlorine D

The final product formed by distilling ethyl alcohol with excess of Cl₂ and Ca(OH)₂is

• CH₃CHO A
• CCl₃CHO B
• CHCl₃ C
• (CH₃)₂O D

Polyester resins have special use in:

• Clothing A
• Paints B
• Emulsion C
• Floor covering D

Formic Acid is obtained from Red out by:

• Distillation A
• Crystallization B
• Filtration C
• sublimation D

The oxidation number of each element of group ll-A is

• 0 A
• +1 B
• +2 C
• -1 D