Question

Give the scientific reason for the following.

In the atmospheric oxygen is available as ${\mathrm{O}}_2$ but not as $\mathrm{O}$.

Answer 1

Dioxygen$\left({\mathrm{O}}_2\right)$:

• The molecules which have two atoms bonded chemically are called diatomic molecules.
• The atomic number of Oxygen is 8.
• The electronic configuration of oxygen can be written as $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^4$
• Oxygen has 6 electrons in the outermost electron, so it needs 2 electrons to fill its outer shell(octet rule).
• Oxygen exists as a diatomic molecule in nature when it is not combined with any other element.
• Oxygen forms ${\mathrm{O}}_2$ molecule because it has the lowest energy level when uncombined.
• Since the stability of an atom is inversely proportional to its energy, ${\mathrm{O}}_2$ is more stable than the uncombined state.