Assign oxidation numbers to each element in (a) \(\mathrm{P}_{2} \mathrm{O}_{5}\) (b) \(\mathrm{NH}_{3}\) (c) \(\mathrm{CO}_{3}{ }^{2-}\) (d) \(\mathrm{S}_{2} \mathrm{O}_{3}^{2-}\) (e) \(\mathrm{N}_{2} \mathrm{H}_{4}\)

Chemical bonding is the force that holds atoms together in molecules and compounds, forming the basis of all substances. There are three primary types of chemical bonds: ionic, covalent, and metallic.

Ionic bonds form when electrons are transferred from one atom to another, leading to the creation of ions with opposite charges that attract each other. For example, sodium and chlorine atoms form an ionic bond in table salt, with sodium losing an electron and chlorine gaining one.

Covalent bonds occur when two atoms share pairs of electrons, generating molecules with shared electron clouds. Oxygen molecules (O₂), for instance, consist of two oxygen atoms sharing a pair of electrons through a covalent bond.

Metallic bonds are found in metals, where electrons are free to move around many positively charged metal ions, thus providing metals with their characteristic properties like conductivity and malleability.

Understanding chemical bonding is crucial when assigning oxidation numbers because the type of bond influences the distribution of electrons among atoms, consequently affecting their oxidation states.

Redox reactions, or oxidation-reduction reactions, are processes where electrons are transferred between atoms, leading to changes in oxidation states. These reactions encompass two half-reactions: oxidation, where an atom, ion, or molecule loses electrons, and reduction, where it gains electrons.

The concept of redox reactions is vital in chemistry because it underpins various chemical processes from metabolic paths in the biological domain to industrial applications like battery operation. In the context of practicing problems or analyzing substances, oxidation states help determine which atom is oxidized and which is reduced.

For example, in a reaction where iron rust forms (Fe₂O₃), iron (Fe) is oxidized as it loses electrons, while oxygen gains them and is reduced. By identifying the changes in oxidation states, students can comprehend the flow of electrons and the transformation of matter in a reaction.

Oxidation states, also known as oxidation numbers, are values assigned to atoms in molecules and ions to describe the degree of oxidation or reduction they undergo. These numerical designations provide insight into the transfer of electrons in chemical reactions, especially redox reactions.

Oxidation states are determined based on a set of rules: elements in their elemental form have an oxidation number of 0, and in most cases, the sum of oxidation numbers in a neutral compound or ion must equate to its overall charge.

For instance, in water (H₂O), oxygen has an oxidation state of -2, while hydrogen has +1. Hence, oxidation numbers play a pivotal role in balancing redox reactions and understanding chemical bonding, as they reflect how electrons are distributed among atoms—crucial for predicting compound behavior and reaction outcomes.