Chemical Bonding: Ionic and Covalent Bonds

Chemical Bonding

Ionic Bonding

• Definition: A type of chemical bond formed through the electrostatic attraction between oppositely charged ions.
• Formation:
  • Typically occurs between metals (which lose electrons) and nonmetals (which gain electrons).
  • Example: Sodium (Na) donates an electron to Chlorine (Cl), forming Na⁺ and Cl⁻ ions.
• Characteristics:
  • High melting and boiling points.
  • Generally soluble in water.
  • Conduct electricity when dissolved in water or molten.

Polar and Nonpolar Bonds

• Covalent Bonds: Formed by the sharing of electron pairs between atoms.
• Nonpolar Covalent Bond:
  • Electrons are shared equally.
  • Occurs between identical atoms (e.g., H₂, O₂) or atoms with similar electronegativities.
• Polar Covalent Bond:
  • Unequal sharing of electrons due to differences in electronegativity.
  • Results in a dipole moment where one end of the bond is slightly negative and the other slightly positive (e.g., H₂O).
• Electronegativity Scale:
  • The difference in electronegativity determines bond type:
    • 0 - 0.4: Nonpolar
    • 0.5 - 1.7: Polar

    • 1.7: Ionic (more than 50% ionic character).

Metallic Bonding

• Definition: A type of bonding found in metals where electrons are delocalized and shared among a lattice of positively charged ions.
• Characteristics:
  • High electrical and thermal conductivity.
  • Malleability and ductility due to the ability of metal atoms to slide over one another.
  • Luster due to the ability to reflect light.

Bonding Theories

• VSEPR (Valence Shell Electron Pair Repulsion):

  • Predicts the geometry of molecules based on the repulsion between electron pairs in the valence shell.
  • Key shapes include linear, trigonal planar, tetrahedral, bent, and octahedral.
  • Lone pairs exert more repulsion than bonding pairs, affecting molecular shapes.

• Hybridization:

  • The concept where atomic orbitals mix to form new hybrid orbitals for bonding.
  • Types include:
    • sp: Linear geometry (180°)
    • sp²: Trigonal planar (120°)
    • sp³: Tetrahedral (109.5°)
    • sp³d: Trigonal bipyramidal (90° and 120°)
    • sp³d²: Octahedral (90°)

Covalent Bonding

• Definition: Chemical bonding resulting from the sharing of electron pairs between atoms.
• Types:
  • Single bond: One pair of shared electrons (e.g., H-H).
  • Double bond: Two pairs of shared electrons (e.g., O=O).
  • Triple bond: Three pairs of shared electrons (e.g., N≡N).
• Properties:
  • Variable melting and boiling points.
  • Poor conductivity in solid and liquid states.
  • Generally insoluble in water but soluble in organic solvents.

Ionic Bonding

• A type of chemical bond formed through the electrostatic attraction between oppositely charged ions.
• Typically occurs between metals (which lose electrons) and nonmetals (which gain electrons).
• Example: Sodium (Na) donates an electron to Chlorine (Cl), forming Na⁺ and Cl⁻ ions.
• High melting and boiling points.
• Generally soluble in water.
• Conduct electricity when dissolved in water or molten.

Polar and Nonpolar Bonds

• Covalent Bonds: Formed by the sharing of electron pairs between atoms.
• Nonpolar Covalent Bond:
  • Electrons are shared equally.
  • Occurs between identical atoms (e.g., H₂, O₂) or atoms with similar electronegativities.
• Polar Covalent Bond:
  • Unequal sharing of electrons due to differences in electronegativity.
  • Results in a dipole moment where one end of the bond is slightly negative and the other slightly positive (e.g., H₂O).
• Electronegativity Scale:
  • The difference in electronegativity determines bond type:
    • 0 - 0.4: Nonpolar
    • 0.5 - 1.7: Polar

    • 1.7: Ionic (more than 50% ionic character).

Metallic Bonding

• A type of bonding found in metals where electrons are delocalized and shared among a lattice of positively charged ions.
• High electrical and thermal conductivity.
• Malleability and ductility due to the ability of metal atoms to slide over one another.
• Luster due to the ability to reflect light.

Bonding Theories

• VSEPR (Valence Shell Electron Pair Repulsion):
  • Predicts the geometry of molecules based on the repulsion between electron pairs in the valence shell.
  • Key shapes include linear, trigonal planar, tetrahedral, bent, and octahedral.
  • Lone pairs exert more repulsion than bonding pairs, affecting molecular shapes.
• Hybridization:
  • The concept where atomic orbitals mix to form new hybrid orbitals for bonding.
  • Types include:
    • sp: Linear geometry (180°)
    • sp²: Trigonal planar (120°)
    • sp³: Tetrahedral (109.5°)
    • sp³d: Trigonal bipyramidal (90° and 120°)
    • sp³d²: Octahedral (90°)

Covalent Bonding

• Chemical bonding resulting from the sharing of electron pairs between atoms.
• Types:
  • Single bond: One pair of shared electrons (e.g., H-H).
  • Double bond: Two pairs of shared electrons (e.g., O=O).
  • Triple bond: Three pairs of shared electrons (e.g., N≡N).
• Properties:
  • Variable melting and boiling points.
  • Poor conductivity in solid and liquid states.
  • Generally insoluble in water but soluble in organic solvents.

Explore the fundamentals of chemical bonding in this quiz, focusing on ionic and covalent bonds. Understand how these bonds are formed, their characteristics, and the distinction between polar and nonpolar bonds. Perfect for chemistry enthusiasts wanting to solidify their knowledge!