IONIC AND COVALENT BONDS (KSSM FORM 4)

What is the difference between an Ionic bond and Covalent bond?

• Ionic - Transfer of electrons

  Covalent - Sharing of electrons

• Ionic - Sharing of electrons

  Covalent - Transfer of electrons

• Ionic - Sharing of electrons

  Covalent - Sharing of electrons

• Ionic - Transfer of electrons

  Covalent - Transfer of electrons

Answer explanation

• Ionic bond: This type of bond occurs when one atom donates an electron(s) to another atom. This transfer of electrons creates ions: a positively charged cation and a negatively charged anion. The electrostatic attraction between these oppositely charged ions forms the ionic bond.

• Covalent bond: In a covalent bond, atoms share electrons to achieve a stable electron configuration. This sharing can be equal (nonpolar covalent bond) or unequal (polar covalent bond).

Ionic compound is formed when ion with opposite charges were attracted by each other by a force named _______ .

• Van Der Waals Force

• Strong Electrostatic Force

• Intermolecular Force

• London Dispersion Force

Answer explanation

• Strong Electrostatic Force: This is the correct answer. Ionic compounds form when ions with opposite charges are strongly attracted to each other due to this force. The electrostatic force arises from the attraction between positively charged cations and negatively charged anions.

• Van Der Waals Force: This is a weak intermolecular force that arises from temporary fluctuations in electron density. It is not strong enough to hold ions together in an ionic compound.

• Intermolecular Force: This is a general term for forces that exist between molecules. While it includes electrostatic forces, it is not specific to the strong attraction between ions in an ionic compound.

• London Dispersion Force: This is a type of Van Der Waals force, and as mentioned above, it is too weak to form ionic bonds.

In ionic bond, metal atom ______ valence electrons to form ______ .

• Donate, Positive ion

• Donate, Negative ion

• Share, Positive ion

• Share, Negative ion

Answer explanation

In an ionic bond, a metal atom typically donates its valence electrons to a nonmetal atom. By losing electrons, the metal atom becomes a positive ion or cation. This is because it now has more protons than electrons, resulting in a net positive charge.

Double bond is formed when _________ shared _________ pair(s) of electrons.

• two, four

• two, two

• one, four

• one, two

Answer explanation

A double bond is formed when two atoms share two pairs of electrons. This means that there are a total of four electrons involved in the bond. Double bonds are stronger and shorter than single bonds.

Covalent bonds are formed when _____ atoms share electrons to achieve a stable duplet or octet electron arrangement

Answer explanation

Covalent bonds primarily occur between non-metal atoms. These atoms tend to have high electronegativities, meaning they strongly attract electrons.

By sharing electrons, non-metal atoms can complete their outermost electron shell (either by achieving a duplet for hydrogen or helium, or an octet for other elements) and attain a more stable electron configuration.

This sharing of electrons results in the formation of a covalent bond.

Describe the process of forming a water molecule.

• Two hydrogen atoms donate their electron with an oxygen atom, forming two covalent bonds.

• Two hydrogen atoms share their electrons with an oxygen atom, forming two covalent bonds.

• Two hydrogen atoms share their electrons with an oxygen atom, forming a covalent bond.

• Two hydrogen atoms donate their electron to an oxygen atom, forming a covalent bond.

Answer explanation

A water molecule, H₂O, is formed when two hydrogen atoms share their electrons with a single oxygen atom. This sharing of electrons results in the formation of two covalent bonds.

Each hydrogen atom shares one electron with the oxygen atom, and the oxygen atom shares two electrons, one with each hydrogen atom. This arrangement allows all three atoms to achieve a stable electron configuration.

Which of the below is an example(s) of a covalent compound.

• 
• 
• 
• 

Answer explanation

Covalent compounds are formed when non-metal atoms share electrons to achieve a stable electron configuration. In the case of H₂O and Cl₂, both elements are non-metals and form covalent bonds by sharing electrons.

AlCl₃ and MgCl₂ are not covalent compounds. They are ionic compounds because they involve a metal (Al or Mg) and a non-metal (Cl). In ionic compounds, there is a transfer of electrons, not sharing, between the metal and non-metal atoms.

What is the difference between a polar covalent bond and a nonpolar covalent bond?

• Polar covalent bonds involve the sharing of electrons, while nonpolar covalent bonds involve the transfer of electrons.

• Polar covalent bonds involve the equal sharing of electrons, while nonpolar covalent bonds involve the unequal sharing of electrons.

• Polar covalent bonds involve the unequal sharing of electrons, while nonpolar covalent bonds involve the equal sharing of electrons.

• None of the above.

Answer explanation

In a covalent bond, atoms share electrons. However, the sharing may not always be equal.

• Nonpolar covalent bond: In this type of bond, the electrons are shared equally between the two atoms. This occurs when the two atoms have the same electronegativity, meaning they pull on the shared electrons with equal force.  

• Polar covalent bond: In this type of bond, the electrons are shared unequally between the two atoms. This happens when one atom has a higher electronegativity than the other. The more electronegative atom pulls the shared electrons closer to itself, creating a partial negative charge on that atom and a partial positive charge on the less electronegative atom. This unequal sharing of electrons results in a polar bond.

Diagram shows an electron arrangement of the Y ion. What is the number of valence electron for Atom Y ?

• 1

• 2

• 8

• 6

Answer explanation

A Lewis structure of Y with a +2 charge indicates that the atom has lost two electrons. Since the number of valence electrons is the number of electrons in the outermost shell, and Y has lost two electrons, it originally had 2 valence electrons.

Classify which of these refers to ionic bond.

• Electron movement

• Formation of ion

• Share electron

• Between non-metal atoms

Answer explanation

Ionic bonds involve the transfer of electrons between atoms. This transfer results in the formation of ions, which are atoms that have gained or lost electrons. The oppositely charged ions are then attracted to each other through a strong electrostatic force, forming an ionic bond.

Key characteristics of ionic bonds:

• - Electron movement: Electrons are transferred from one atom to another.

• - Formation of ions: Cations (positive ions) and anions (negative ions) are formed.

• - Strong electrostatic attraction: The oppositely charged ions are strongly attracted to each other.

• - Typically between metals and non-metals: Metals tend to lose electrons, while non-metals tend to gain electrons.