Chemical Bonding Quiz

Chemical Bonding: An Overview

• Chemical bonds enable the formation of molecules, crystals, and other structures through the lasting attraction between atoms or ions.

• Chemical bonds may result from the electrostatic force between oppositely charged ions as in ionic bonds, or through the sharing of electrons as in covalent bonds.

• The strength of chemical bonds varies considerably, with "strong bonds" or "primary bonds" such as covalent, ionic, and metallic bonds, and "weak bonds" or "secondary bonds" such as dipole-dipole interactions, the London dispersion force, and hydrogen bonding.

• Atoms are held together by chemical bonds, which determine the structure and properties of matter.

• The octet rule and VSEPR theory are examples of simplified rules and other theories that allow chemists to predict the strength, directionality, and polarity of bonds.

• More sophisticated theories include valence bond theory, molecular orbital theory, and ligand field theory.

• Covalent bonds exist between two identifiable atoms and have a direction in space, while ionic bonds have no particular orientation in space.

• Metallic bonding involves each atom in a metal donating one or more electrons to a "sea" of electrons that reside between many metal atoms.

• Early speculations about the nature of the chemical bond date back to the 12th century, and key developments in the field include Sir Isaac Newton's atomic bonding theory and Niels Bohr's model of a nuclear atom with electron orbits.

• Strong chemical bonds are the intramolecular forces that hold atoms together in molecules and rely on the electrostatic attraction between the protons in nuclei and the electrons in the orbitals.

• The types of strong bond differ due to the difference in electronegativity of the constituent elements, with a large difference in electronegativity leading to more polar (ionic) character in the bond.

• Ionic bonding is a type of electrostatic interaction between atoms that have a large electronegativity difference, with an electronegativity difference of over 1.7 being likely to be ionic while a difference of less than 1.7 is likely to be covalent.Types of Chemical Bonding

• Ionic bonding involves transfer of electrons from one atom to another to form ions with opposite charges.

• Ionic bonding occurs mainly in metal salts, with ionic charges between -3e to +3e.

• Ionic bonds lead to formation of ionic crystals, where each ion is surrounded by ions of opposite charge.

• In covalent bonding, two or more atoms share valence electrons more or less equally.

• Covalent bonds can be non-polar or polar, depending on the electronegativity difference between the bonded atoms.

• Molecules formed primarily from non-polar covalent bonds are immiscible in polar solvents but soluble in non-polar solvents.

• Double bonds consist of two shared pairs of electrons, one in a sigma bond and one in a pi bond.

• Triple bonds consist of three shared electron pairs, forming one sigma and two pi bonds.

• Coordinate covalent bonds occur when two shared bonding electrons are from the same atom.

• Metallic bonding involves delocalized bonding electrons over a lattice of atoms.

• Weak intermolecular forces such as van der Waals forces, Keesom forces, London dispersion forces, and hydrogen bonds can cause molecules to attract or repel each other.

• Covalent bonds are better understood by valence bond theory or molecular orbital theory.