Chemistry: Types of Chemical Bonds

Study Notes

Ionic Bonds:
- Formed between two atoms with a large difference in electronegativity
- One atom loses an electron (becomes a cation) and the other gains an electron (becomes an anion)
- Electrostatic attraction between oppositely charged ions holds them together
Covalent Bonds:
- Formed between two atoms sharing one or more pairs of electrons
- Can be polar or nonpolar depending on the difference in electronegativity
- Can be single, double, or triple bonds depending on the number of shared electron pairs
Hydrogen Bonds:
- A type of intermolecular force between molecules
- Formed between a hydrogen atom bonded to a highly electronegative atom (e.g. oxygen, nitrogen) and another electronegative atom
- Weak compared to ionic and covalent bonds, but important in biomolecules

Valence Shell Electron Pair Repulsion (VSEPR) Theory:
- Predicts the shape of molecules based on the arrangement of electron pairs around the central atom
- Electron pairs arrange themselves to minimize repulsion and maximize distance
Molecular Orbital (MO) Theory:
- Describes the distribution of electrons within a molecule
- Combines atomic orbitals to form molecular orbitals, which can be bonding, antibonding, or non-bonding

Bond Length: the distance between the nuclei of two bonded atoms
Bond Strength: the energy required to break a bond, measured in kilojoules per mole (kJ/mol)
Bond Polarity: the distribution of electrons within a covalent bond, resulting in a partial positive and negative charge
Electronegativity: the ability of an atom to attract electrons in a covalent bond, measured on the Pauling scale

Ionic bonds form between two atoms with a large difference in electronegativity, resulting in the transfer of electrons and the creation of ions with opposite charges.
In ionic bonds, one atom loses an electron to become a cation, while the other gains an electron to become an anion.
The electrostatic attraction between oppositely charged ions holds them together in ionic bonds.
Covalent bonds form between two atoms sharing one or more pairs of electrons, resulting in a molecule with a shared electron cloud.
Covalent bonds can be polar or nonpolar, depending on the difference in electronegativity between the atoms involved.
The type of covalent bond (single, double, or triple) is determined by the number of shared electron pairs.
Hydrogen bonds are a type of intermolecular force between molecules, formed between a hydrogen atom bonded to a highly electronegative atom and another electronegative atom.
Hydrogen bonds are weak compared to ionic and covalent bonds, but play a crucial role in the structure and function of biomolecules.

Valence Shell Electron Pair Repulsion (VSEPR) Theory predicts the shape of molecules based on the arrangement of electron pairs around the central atom.
Electron pairs arrange themselves to minimize repulsion and maximize distance in VSEPR Theory.
VSEPR Theory is used to predict the shape of molecules, including bond angles and molecular geometry.
Molecular Orbital (MO) Theory describes the distribution of electrons within a molecule, combining atomic orbitals to form molecular orbitals.
Molecular orbitals can be bonding, antibonding, or non-bonding, depending on the arrangement of electrons.
MO Theory provides a more detailed understanding of electron distribution and bonding in molecules.

Bond length is the distance between the nuclei of two bonded atoms, measured in picometers (pm).
Bond strength is the energy required to break a bond, measured in kilojoules per mole (kJ/mol).
Bond polarity occurs when there is an unequal distribution of electrons within a covalent bond, resulting in a partial positive and negative charge.
Electronegativity is the ability of an atom to attract electrons in a covalent bond, measured on the Pauling scale, which ranges from 0 to 4.0.