ECAT Pre Engineering Chemistry Chapter 1 MCQ Test With Answer

• 99.2% A
• 99.5% B
• 90.5% C
• 96.2% D

• 84.84 % A
• 89.89% B
• 81.81% C
• 90.90% D

A compound X contains 50% sulphur and 50% oxygen by mass. What is the empirical formula of compound X?

• SO A
• SO₂ B
• SO₃ C
• SO₄ D

Ascorbic acid contains 40.92% carbon, 4.58%, hydrogen and 54.4% oxygen. The empirical formula is

• C₃H₄O₃ A
• C₂H₄O₃ B
• C₃H₅O₄ C
• C₂H₃O₁ D

CL₂, N₂ and O_{2 are:}

• Diatomic molecules

  A

• Hetero atomic molecules

  B

• Poly-atomic molecules

  C
• Mono-atomic molecules D

• N₂O₄is limiting reactant A
• N₂H₄is the limiting reactant B
• Reactants are completely converted to the products C
• Reactions is reversible D

Formation of a cation is:

• Exothermic process A
• Non-endothermic process B
• Endothermic process C
• None of above D

The amount of products obtained from the balanced chemical equation is regarded as

• Theoretical yield A
• Actual yield B
• % yield C
• Experimental yield D

A molecule of haemoglobin is made up if nearly

• 10,000 atoms A
• 50,000 atoms B
• 2500 atoms C
• 1500 atoms D

The mass of one mole of proton is

• 1.008 g A
• 0.184 g B
• 1.673 g C
• 1.008 mg D

Who one mole of each of the following is completely burned in oxygen, which gives the largest mass of carbon dioxide?

• Carbon monoxide A
• Diamond B
• Ethane C
• Methane D

The mass of Al₂S₃formed when 20 grams Al reacts completely with S is

• 60 g A
• 50 g B
• 50.55 g C
• 55.55 g D

A beaker contains 9 grams of water. The number of H-atoms is

• 6.02 x 1023 A
• 3.01 x 1023 B
• 6.02 x 1024 C
• 3.01 x 1024 D

Objects of the size of an atom can be observed in

• An electron microscope A
• An x-ray spectrum B
• Atomic absorption spectrum C
• A visible spectrum D

Al³⁺is a symbol for aluminium

• Atom A
• Ion B
• Cation C
• Anion D

What is the maximum mass of aluminium which can be obtained from 240g of aluminium oxide Al₂O₃?

• 26 g A
• 127 g B
• 51 g C
• 108 g D

The relative abundance of the ions with a definite m/e value is measured by

• High pressure of vapours A
• Strength of electric current measured B
• Quantity of fast moving electrons C
• Electron gas D

A molecular ion is formed by

• Passing a high energy electron beam through gaseous molecule A
• Dissolving a salt i dilute acid B
• Passing electric current through molten salt C
• Passing electricity through aqueous solutions D

The percentage of H is the highest in

• CH₄ A
• NH₃ B
• H₂SO₄ C
• C₆H₁₂O₆ D

The atom of an element is

• The smallest particle A
• The fundamental particle B
• The independent particle C
• The charged particle 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

Which of the sub-atomic particles is not charged

• Electron A
• Proton B
• Neutron C
• All of them D

The negatively charged particles are called

• Cation A
• Radical B
• Anion C
• Positron D

The pressure of vapours when sent to the ionization chamber in mass spectrometer is

• 10^-5to 10^-6torr A
• 10^-6to 10^-7torr B
• 10^-7to 10^-8torr C
• 10^-3to 10^-4torr D

A compound contains one atom of oxygen and % of O 34.78, then molecular mass of compound is

• 46 A
• 78 B
• 110 C
• 180 D

One mole of SO₂contains

• 6.02 x 10²³atoms of oxygen A
• 18.1 x 10²³, molecules of SO₂ B
• 6.02 x 10²³ atoms of sulphur C
• 4 gram atoms of SO₂ D

A beaker contains 9 grams of water. The number of H atoms is

• 6.02 x 10²³ A
• 3.01 x 10²³ B
• 6.02 x 10²⁴ C
• 3.01 x 10²⁴ D

Where energy is released during a reaction it is

• Exothermic reaction A
• Endothermic reaction B
• A free radical reaction C
• A bond breaking reaction D

First atomic theory was put forward by an English school teacher:

• Maxewell A
• Newton B
• Sanger C
• John Dalton D

C₆H₁₂O₆and C₁₂H₂₂O₁₁ are:

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

• Hetero atomic molecules

  D