ECAT Pre Engineering Chemistry Chapter 1 MCQ Test With Answer

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

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

• 
  A
• 
  B
• 
  C
• 
  D

Which one of the following step is not involved in determination of empirical formula

• Determination % of each element A
• Determination of gram atom of each element B
• Determination of isotopes of each element C
• Determination of atomic ratio of element D

Which of the sub-atomic particles is not charged

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

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

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

The atom of an element is

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

Mass spectrometer measures the

• Exact mass of an element A
• Average mass of an element B
• The number of elements present in a molecule C
• m/e value of a positive ion D

When an electron is added to a uni positive ion we get:

• Cation A
• Molecule B
• Neutral atom C
• Anion D

• 300 cm³ A
• 200 cm³ B
• 150 cm³ C
• 100 cm³ 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

What is the volume in cm³of 3.01 x 10²³molecules of O₂gas at S.T.P

• 1000 cm³ A
• 11000 cm³ B
• 1120 cm³ C
• 11200 cm³ D

Molecules of High molecular weight usually greater than 10,000 are called:

• Macro molecules A
• Mega molecules B
• Poly molecules C
• Gega molecules D

Atoms can be evident by use of electron microscope, field ionization microscope and:

• x-rays A
• Video camera
  
  
  B
• Telescope C
• Compound microscope D

Benzene is stable to:

• Oxidation A
• Nitration B
• KMnO₄ C
• SULPHONATION D

Metal tend to lose electrons, becoming:

• Metals

  A

• Positively charged

  B

• Negatively charged

  C

• (a)And (c)

  D

Which of the following compounds contains the highest percentage by mass of nitrogen?

• Ammonia, NH₃ A
• Ammonium carbamate, NH₂CO₂NH₄ B
• Ammonium carbonate, (NH₄)₂CO₃ C
• Hydrazine, N₂H₄ 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

The mass of sulphur which combines with 24 grams oxygen to form SO₂

• 32 gram A
• 24 gram B
• 8 gram C
• 12 gram D

The number of isotopes of gold is

• 3 A
• 1 B
• 2 C
• 4 D

A balloon contains 0.02 gram of H₂gas, it contains H₂molecules

• 6.02 x 10²³ A
• 3.01 x 10²² B
• 6.02 x 10²¹ C
• 3.01 x 10²¹ 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

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

Isotopes differ in the

• Number of neutrons A
• Number of protons B
• Number of electrons C
• Number of atoms D

Which of the following statements is not true?

• Isotopes with even atomic masses are comparatively abundant A
• Isotopes with even atomic masses are comparatively abundant B
• Isotopes with even atomic masses and even atomic numbers are comparatively abundant C
• Isotopes with even atomic masses and odd atomic number are comparatively abundant D

Determination of atomic masses and invention of system of writing symbols was made by:

• J. Berzelius A
• Democritus B
• Dalton C
• None of above D

The percentage of H is the highest in

• CH₄ A
• NH₃ B
• H₂SO₄ C
• C₆H₁₂O₆ 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 relative abundance of Pb isotopes is 1.5% Pb²⁰⁴, 23.6% Pb²⁰⁶, 22.6% Pb²⁰⁷, 52.3% Pb²⁰⁸The relative atomic mass of Pb is

• 207.94 A
• 208.24 B
• 206.94 C
• 207.24 D