ECAT Pre Engineering Chemistry Chapter 1 MCQ Test With Answer

Atoms and molecules can either gain or lose electrons, forming charge particles called:

• Positrons

  A

• Photons

  B

• Ions

  C

• Electrons

  D

The atom of an element is

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

C₆H₁₂O₆and C₁₂H₂₂O₁₁ are:

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

• Hetero atomic molecules

  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

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

3.01 x 10²²Ag⁺ions is present in

• 85 grams AgNO₃ A
• 0.85 g AgNO₃ B
• 8.5 g AgNO₃ C
• 18.5 g AgNO₃ D

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

If four moles of sulpur dioxide are oxidised to sulphur trioxide, how many moles of oxygen molecules are required

• 0.5 A
• 1.0 B
• 1.5 C
• 2.0 D

• 8 g A
• 16 g B
• 32 g C
• 24 g D

Formation of a cation is:

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

The number of subatomic particles in atoms sidcovered is more than:

• 110 A
• 100 B
• 125 C
• 90 D

CL₂, N₂ and O_{2 are:}

• Diatomic molecules

  A

• Hetero atomic molecules

  B

• Poly-atomic molecules

  C
• Mono-atomic molecules D

The negatively charged particles are called

• Cation A
• Radical B
• Anion C
• Positron 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

A compound having empirical formula C₃H₃O and its molecular mass is 110.02. Its molecular formula is

• C₃H₃O A
• C₆H₆O₂ B
• C₉H₉O₃ C
• C₃H₆O₂ D

The number of atoms present in molecule determines its:

• Molecularity A
• Atomicity B
• Basicity C
• Acidity D

NH₃, HCL, H₂O, HL are:

• Diatomic molecules

  A

• Poly-atomic molecules

  B

• Mono-atomic molecules

  C

• Hetero atomic molecules

  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

In molecules kinetic and potential energies are:

• Definite A
• Moderate B
• Indefinite C
• None of above 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 largest number of molecules are present in

• 3.6 g of H₂O A
• 4.8 g of C₂H₅OH B
• 2.8 g of CO C
• 5.4 g of N₂O₅ D

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

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

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

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

Al³⁺is a symbol for aluminium

• Atom A
• Ion B
• Cation C
• Anion D

One of the following statements is incorrect

• Actual yeild is always less than the theoretical yield A
• The formula of a compound is not definite B
• Law of conservation of mass is applied in stoictiometry C
• Boyles law is applied in stoichiometry D

The percentage of which element in the organic compound is determined by the difference method

• Carbon A
• Hydrogen B
• Nitrogen C
• Oxygen D

• 32 g A
• 3.2 g B
• 5.6 g C
• 9.6 g D