1.2 - Structure and Bonding

Structure and Bonding

Higher Chemistry 1.2

Intramolecular bonds are the bonds found within molecules, they all have different properties and can be arranged into a bonding continuum. The types of intramolecular bonds are:

• metallic
• pure covalent
• polar covalent
• ionic

Metallic bonding consists of atoms losing their outer electrons to a pool of delocalised electrons, with each atom losing one or more electrons they become positively charged ions. The metal ions are attracted to the pool of electrons and, because the electrons are free to move, they conduct electricity.

Covalent bonding is the electrostatic force of attraction between positive nuclei and negative electrons. The bond itself is a shared pair of electrons. 

Pure covalent bonds exist between two atoms with the same electronegativities and have no ionic character. Examples of pure covalent bonds: diatomic molecules, S_8, P₄, C₆₀ (covalent molecular) boron, carbon - in the form of diamond and graphite - and silicon (covalent network)

If an atom is non-polar, it will have an electronegativity value between 0 and 0.4 and if the polar bonds in a larger molecule cancel each other out because of symmetry

Polar covalent bonds are formed when a shared pair of electrons aren't shared equally. The atoms have different electronegativities. The atom with the stronger electronegativity will become slightly negative and the atom with the weaker electronegativity will become slightly positive. This is known as…