Answer : Option C) The Octet Rule
Explanation : Atoms have a tendency to complete their outer energy level. This is known as Octet Rule.
The octet rule is a chemical rule of thumb which reflects the observation, that atoms of main-group elements tends to combine in such a way that each atom gets eight electrons in its valence shell, which gives it the same electron configuration as that of a noble gas.
In short, the tendency of an atom to fill its valence shell and attain a stable state it acquires or donates the electron is called as octet rule.
In an acidic solution, the concentration of H+ is greater than the concentration of OH-. The pH will be less than 7.
In a basic solution, the concentration of OH- is greater than the concentration of H+. The pH will be greater than 7.
In a neutral solution, the concentration of H+ ions to OH-ions will be equal, and will therefore have a pH of 7. (This is due to water autoionization, which we usually ignore because it is small in other circumstances.)
