The Charged Particles

IONS

The electrically charged particle that is formed whenever an atom loses or gains one or more electrons is called an ion.

When an atom of hydrogen loses one electron, it forms a hydrogen ion.

 

Cation

v The cation is a positively charged ion.

v It is formed whenever an atom loses one or more electrons.

When a sodium atom (Na) loses an electron, it gives sodium ion (Na⁺). Na⁺ is a cation.

     

 

v The charge on any ion is shown as a superscript to the symbol of the corresponding element.

  

Anion

v The anion is a negatively charged ion.

v It is formed whenever an atom gains one or more electrons.

When a chlorine atom (Cl) gains an electron, it gives chloride ion (Cl^–). Cl^– is an anion.