ECAT Pre Engineering MCQ Test With Answer for Chemistry Full Book

Which for the following has no dipole moment

• HCI A
• H₂S B
• H₂O C
• CO₂ D

The bond order in No is 2.5 while that in NO⁺is 3.Which of the following statements is true for these two species?

• Bond length in NO⁺is greater than in NO A
• Bond length in unpredictable B
• Bond length in NO⁺is equal to that in NO C
• Bond length in NO is greater than in NO⁺ D

The gases can be converted into liquids by

• increasing the pressure only A
• Lowering temperature and increasing pressure B
• Increasing pressure and bringing temperature below critical point C
• Lowering temperature only D

A 4f orbital has

• one node A
• two node B
• three node C
• four nodes D

Shahi Qilla may be destroyed by

• Flood in Ravi A
• Temperature mediated spoilage of marble B
• Air pollutants from Lahore chemical industries C
• All the above D

Any other aldehyde except formaldehyde on reaction with Grignard's will produce

• Secondary alcohol A
• Primary alcohol B
• Tertiary alcohol C
• Aromatic alcohol D

How many moles of oxygen, O₂are needed for the complete combustion of two moles of butane C₄H₁₀?

• 2 A
• 8 B
• 10 C
• 13 D

Both E₁and E₂mechanism can be shown by

• 1° - RX A
• 2° - RX B
• 3° - RX C
• None of these D

The graph between pressure and volume at constant temperature for a gas is

• Isobaric A
• Isothermal B
• Isotherm C
• None of above D

Which of the following is not a colligative property?

• Depression in freezing point A
• Elevation of boiling point B
• Osmotic pressure C
• Modification of refractive index D

When an electric current is passed through discharge tube at low pressure, cathode rays are emitted from cathode these rays consist of:

• Alpha rays. A
• Negative particles. B
• Electromagnetic rays. C
• Positive particles. D

During nitration of benzene, the active nitrating agent is:

• NO₃^-1 A
• NO₂₊ B
• NO₂^-1 C
• HNO₃ D

Which of the following half molar solutions will have lowest freezing point

• Solution of non-volatile, none electrolyte A
• Solution of non volatile, weak electrolyte B
• Solution of non volatile strong electrolyte C
• Solution of volatile, non electrolyte D

Which is possible in ethers?

• Reactivity high A
• Oxidation and reduction B
• Reactivity towards bases C
• Towards acids D

Which one gives acidic reactions?

• CH₃----C≡C-------CH₃ A
• CH₃-----CH₂-----HC=CH----CH₂ B
• CH₃----CH=CH₂ C
• CH₃-----C≡CH D

If the standard electrode potential of CU²⁺/Cu electrode is 0.34 V, what is the electrode potential of 0.01 M concentration of Cu²⁺? (T=298)

• 0.399 V A
• 0.281 V B
• 0.222 V C
• 0.176 V D

DNA is a polynucleic acid. The monomer is known as a nucleotide. What is not the component of the nucleoptide

• Phosphate group A
• Deoxy ribose sugar B
• Uracil base C
• Adenine base D

General formula of aliphatic carboxylic acids:

• R---OH A
• R----COH B
• R----CO---R C
• RCOOH D

Boyle's law does not fall even

• Temperature is extremely high A
• Pressure is extremely high B
• Mixture of gases is taken C
• all of above D

The molecules of CO₂in dry ice from the

• Ionic crystalls A
• Covalent crystals B
• Molecular crystals C
• Any type of crystal D

Which one does not declourized KMnO₄

• Alkenes A
• Alkynes B
• Bezene C
• All above D

The quantum number which describes the shape of the orbital is

• Principle quantum number A
• Spin quantum number B
• Azimathal quantum number C
• Magnetic quantum number D

Refrectrometric method is used when

• Reactions involving absorption of I.R. or U. V A
• Reactions involving change of refractive index B
• Reactions involving ions C
• Change of optical activity D

Which term was derived from atomos?

• atom A
• hydrocarbon B
• aromatic C
• aliphatic D

• Increases A
• Decreases B
• Remains same C
• Cannot be predicted D

What are alloys

• A homogenous mixture of two or more elements A
• A homohenous mixture of metal and a non-metal B
• A homogenous mixture of two or more metals C
• None of the above D

Which of the following metal exhibits more than one oxidation?

• Na A
• Mg B
• Fe C
• Al D

To ensure that ethanol is not used for drinking purpose it is converted to methylated spirit by adding.

• 10% methanol and a little acetone A
• 10% petrol and little diesel B
• 50% Alcohol C
• Only 10% methanol D

The energy of the system and surrounding is conserved. This is a statement of

• Law of mass action A
• Law of definite proportion B
• Law of conservation of energy C
• Second law of thermodynamics D

An oil or fat with no double bond have iodine number:

• Zero A
• 100% B
• 50% C
• minimum D