Question

Give one example of a monovalent polyatomic cation.

Answer 1

Cation:

• It is defined as a positively charged ion that is formed when an atom losses its electron (usually valence electron).
• Since the ion formed is having more number of protons than electrons, hence carries a net positive charge.
• Example of cation is ${\mathrm{Na}}^{+}$which is formed when the outer valence electron of sodium atom is removed.

Monovalent cation:

• An atom that loses only one electron and acquires a net $+1$ positive charge is called a monovalent cation.
• Example; potassium ion (${\mathrm{K}}^{+}$), sodium ion (${\mathrm{Na}}^{+}$) , ammonium ion (${{\mathrm{NH}}_4}^{+}$)etc.

Polyatomic cation:

• An ion with a net positive charge which consists of more than one atom is called a polyatomic cation.
• Example; ammonium ion (${{\mathrm{NH}}_4}^{+}$),.

Thus, the example of a monovalent polyatomic cation is ammonium ion (${{\mathbf{NH}}_{\mathbf{4}}}^{\mathbf{+}}$).