# Atoms and Molecules

Tutormate > CBSE Syllabus-Class 9th Chemistry > Atoms and Molecules

## 06 Ions

• A positively or negatively charged atom or group of atoms is called an ion.
• Cation: A Positively Charged Ion is known as Cation.
• Anion: A Negatively Charged Ion is known as Anion.

SOME COMMON IONS

 Name of ion Symbol (or Formula) Name of Ion Symbol (or Formula) 1. Sodium ion ${\mathrm{Na}}^{+}$ 10. Chloride ion ${\mathrm{Cl}}^{–}$ 2. Potassium ion ${\mathrm{K}}^{+}$ 11. Bromide ion ${\mathrm{Br}}^{–}$ 3. Ammonium ion ${\mathrm{NH}}_{4}^{+}$ 12. Hydroxide ion ${\mathrm{OH}}^{–}$ 4. Magnesium ion ${\mathrm{Mg}}^{2+}$ 13. Nitrate ion ${\mathrm{NO}}_{3}^{–}$ 5. Calcium ion ${\mathrm{Ca}}^{2+}$ 14. Oxide ion ${\mathrm{O}}^{2–}$ 6. Copper (II) ion ${\mathrm{Cu}}^{2+}$ 15. Sulphide ion ${\mathrm{S}}^{2–}$ 7. Zinc ion ${\mathrm{Zn}}^{2+}$ 16. Carbonate ion ${\mathrm{CO}}_{3}^{2–}$ 8. Iron (II) ion ${\mathrm{Fe}}^{2+}$ 17. Sulphate ion ${\mathrm{SO}}_{4}^{2–}$ 9. Aluminium ion ${\mathrm{Al}}^{3+}$ 18. Phosphate ion ${\mathrm{PO}}_{4}^{3–}$

IONIC COMPOUNDS:

The compounds which are made up of ions are known as ionic compounds.