Question

Define monoatomic ion.

Answer 1

• Sometimes atoms become charged by losing or gaining electrons.
• By losing electrons, metals form a positively charged ion known as a cation.
• By gaining electrons, nonmetals form a negatively charged ion known as an anion.
• A monoatomic ion also called a simple ion, is an ion consisting of only one atom.
• They are formed by losing or gaining electrons in the outermost shell of an atom.
• There is no chemical bond between the atoms in the ion.
• If an ion contains more than one atom, even though these atoms are from the same element, it is called a polyatomic ion.

Example: In $\mathrm{Calcium}\mathrm{carbonate}\left({\mathrm{CaCO}}_3\right)$ compound consists of monoatomic ion ${\mathrm{Ca}}^{2+}$and polyatomic ion ${{\mathrm{CO}}_3}^{2-}$.