Question

What is the valency of oxide ion and sulphide ion?

Answer 1

Valency:

• It is the number of hydrogen atoms that combine directly or indirectly with one atom of an element.
• Simply the capacity of an atom to lose, gain or share electrons to complete its octet configuration.
• It is equal to the magnitude of the charge they carry.
• It is a property of an atom in which valency has no sign.
• It is the number of electrons of an atom which uses to combine with atoms of another element.
• It is the combined power of an element.
• In an atom, the valence electrons are the electrons that can be used in combining with other atoms. they are lying in the valance shells(orbitals of the outermost shell)
• for example, Hydrogen has 1 electron, and its valency is one, one electron is needed to complete its outermost shell.

Find the valency for oxygen and sulphur:

• The atomic number of oxygen is 8, and the atomic number of sulphur is 16. Both have the same number of valence electrons in their valence shell, 6.
• By gaining two electrons, they attain the noble gas configuration. Hence, they have 2 valencies.

1. The valency of oxide ion is 2. The symbol is ${\mathrm{O}}^{-2}$.
2. The valency of sulphide ion is 2. The symbol is ${\mathrm{S}}^{-2}$.

Hence, the valency of both ions is same, 2.