Class 9 Chemistry MCQs: Chemical Bonding

MCQs (sample)

Showing 25 questions from this chapter. For a full timed test, use “Start online test”.

1. 1. What are the two types of bonds based on the tendency of an atom to lose, gain, or share electrons?

   • Ionic bonds and Covalent bonds
   • Metallic bonds and Ionic bonds
   • Covalent bonds and Hydrogen bonds
   • Ionic bonds and Metallic bonds
   Answer & explanation

   Correct: Ionic bonds and Covalent bonds

   The two types of bonds are Ionic bonds and Covalent bonds.

2. 2. What are the forces that hold atoms together in substances called?

   • Chemical bonds
   • Noble gases
   • Electrons
   • Molecules
   Answer & explanation

   Correct: Chemical bonds

   The forces that hold atoms together in substances are referred to as chemical bonds.

3. 3. What is an intermolecular force?

   • An attractive force between molecules
   • A force holding atoms within a molecule
   • The force due to gravitational pull
   • An electromagnetic force between electrons
   Answer & explanation

   Correct: An attractive force between molecules

   An intermolecular force is defined as the attractive force that exists between the molecules.

4. 4. What is the general electronic configuration of noble gases?

   • ns2, np6
   • ns2, np4
   • ns2
   • ns2, np5
   Answer & explanation

   Correct: ns2, np6

   Noble gases have a general electronic configuration of ns2, np6, except for helium which is 1s2.

5. 5. What type of particles can a substance contain?

   • Atoms, ions, or molecules
   • Only ions
   • Only molecules
   • Only atoms
   Answer & explanation

   Correct: Atoms, ions, or molecules

   A substance can contain atoms, ions, or molecules as stated in the content.

6. 6. What are the electrons in metals that can move freely called?

   • Free electrons
   • Bound electrons
   • Ionic electrons
   • Valence electrons
   Answer & explanation

   Correct: Free electrons

   In metals, the valence electrons can move freely and are referred to as free electrons.

7. 7. What forms when one atom loses an electron and another atom gains that electron?

   • Cation and Anion
   • Ionic bond
   • Metallic bond
   • Covalent bond
   Answer & explanation

   Correct: Ionic bond

   An ionic bond forms when one atom loses an electron to form a cation, while another atom gains that electron to form an anion.

8. 8. What type of elements are metals classified as based on their behavior in chemical bonding?

   • Electropositive
   • Electronegative
   • Neutral
   • Inert
   Answer & explanation

   Correct: Electropositive

   Metals are electropositive because they tend to lose electrons to become stable.

9. 9. Dipole-dipole interactions occur between which type of molecules?

   • Non-polar molecules
   • Ionic molecules
   • Polar molecules
   • Noble gases
   Answer & explanation

   Correct: Polar molecules

   Dipole-dipole interactions specifically occur between polar molecules.

10. 10. Which group of the periodic table consists of noble gases?

    • Group VIIIA
    • Group VIA
    • Group IA
    • Group IIA
    Answer & explanation

    Correct: Group VIIIA

    Group VIIIA consists of noble gases which are stable and chemically inert.

11. 11. Which factor influences the melting and boiling points of a substance?

    • The type of elementary particles
    • The color of the substance
    • The temperature of the environment
    • The amount of substance
    Answer & explanation

    Correct: The type of elementary particles

    The type of elementary particles is one of the three main factors that determine a substance's properties, including melting and boiling points.

12. 12. What do metal atoms form after losing their valence electrons?

    • Negatively charged ions
    • Neutral atoms
    • Positive ions
    • Molecules
    Answer & explanation

    Correct: Positive ions

    Metal atoms lose their valence electrons and form positive ions.

13. 13. How are ionic compounds characterized in terms of charges?

    • Positive charge equals negative charge
    • Only positive charges are present
    • Only negative charges are present
    • Unequal positive and negative charges
    Answer & explanation

    Correct: Positive charge equals negative charge

    Ionic compounds must have equal total positive and negative charges to remain electrically neutral.

14. 14. What happens when atoms gain or lose electrons?

    • They become radioactive.
    • They acquire the configuration of the next noble gas element.
    • They dissolve in water.
    • They form molecules.
    Answer & explanation

    Correct: They acquire the configuration of the next noble gas element.

    When atoms gain or lose electrons, they acquire the electron configuration of the next noble gas element.

15. 15. Which atoms can form hydrogen bonds according to the content?

    • Carbon, hydrogen, and sulfur
    • Oxygen, nitrogen, and fluorine
    • Chlorine, bromine, and iodine
    • Magnesium, aluminum, and zinc
    Answer & explanation

    Correct: Oxygen, nitrogen, and fluorine

    Hydrogen bonds can form with highly electronegative atoms such as oxygen, nitrogen, and fluorine.

16. 16. What does the octet rule state?

    • Atoms are most stable with eight electrons in the valence shell.
    • Atoms are most stable with two electrons in the valence shell.
    • Atoms prefer to have four electrons in their valence shell.
    • Atoms do not have a preference for electron numbers.
    Answer & explanation

    Correct: Atoms are most stable with eight electrons in the valence shell.

    The octet rule states that an atom is most stable when its valence shell contains eight electrons.

17. 17. What type of bonding keeps the carbon atoms together in graphite?

    • Ionic bonding
    • Covalent bonding
    • Metallic bonding
    • Hydrogen bonding
    Answer & explanation

    Correct: Covalent bonding

    In graphite, carbon atoms are connected by single covalent bonds in a hexagonal arrangement.

18. 18. What is formed as a result of the delocalized electrons in metals?

    • Electron sea
    • Ionic lattice
    • Molecular cloud
    • Covalent bond
    Answer & explanation

    Correct: Electron sea

    Delocalized electrons form a structure known as the electron sea.

19. 19. What is a key feature of covalent bonds?

    • They involve sharing of electrons between atoms
    • They involve transfer of electrons from one atom to another
    • They are formed between metals only
    • They are weaker than ionic bonds
    Answer & explanation

    Correct: They involve sharing of electrons between atoms

    Covalent bonds are formed by the mutual sharing of electrons between two atoms.

20. 20. What do non-metals tend to do in terms of electron behavior?

    • Lose electrons.
    • Gain electrons.
    • Share electrons.
    • Remain neutral.
    Answer & explanation

    Correct: Gain electrons.

    Non-metals are electronegative because they gain electrons to become stable.

21. 21. What is the effect of hydrogen bonding on substances like water?

    • It decreases the boiling point
    • It has no effect
    • It helps determine their properties
    • It makes them non-polar
    Answer & explanation

    Correct: It helps determine their properties

    Hydrogen bonding is extremely important in determining properties of substances like water.

22. 22. Who introduced the concept of the octet rule?

    • G. N. Lewis
    • Dmitri Mendeleev
    • Marie Curie
    • Albert Einstein
    Answer & explanation

    Correct: G. N. Lewis

    G. N. Lewis introduced the concept of the octet rule in 1916.

23. 23. Why do ionic compounds like sodium chloride conduct electricity when dissolved in water?

    • They have free electrons
    • They ionize and allow ions to move freely
    • They are in a solid state
    • They have weak intermolecular forces
    Answer & explanation

    Correct: They ionize and allow ions to move freely

    Ionic compounds conduct electricity when dissolved because they ionize, allowing ions to move freely.

24. 24. What type of bonding occurs in metals?

    • Ionic bonding
    • Covalent bonding
    • Metallic bonding
    • Polar bonding
    Answer & explanation

    Correct: Metallic bonding

    The bonding that occurs in metals is specifically termed metallic bonding.

25. 25. What is formed when two hydrogen atoms share one pair of electrons?

    • Single covalent bond
    • Double covalent bond
    • Triple covalent bond
    • Ionic bond
    Answer & explanation

    Correct: Single covalent bond

    A single covalent bond is formed when two atoms share one pair of electrons.