Question

Difference between polyatomic ion and diatomic ion

Answer 1

Diatomic molecules are atoms that bond to their same element, some of the diatomic molecules are Br2, Cl2, I2, N2, H2, O2, F2 . Their net charge is zero for the entire molecule. As for polyatomic ions, Such as H3O+, OH−, HCO−3, SO2−4, Their net charge is not zero, therefore, they are ready to bond with some other cations.

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Answer 2

Polyatomic ion-
These type of ions are molecules in which they are  bonded with different atom are known as Polyatomic ions or molecules. Example -HCO−3, H3O+, OH− ,etc.

Diatomic ion- 
These type of ions are molecules in which atoms are  bonded with there same atom are known as diatomic ions . Example - N2, H2, O2 ,Br2, Cl2 ,etc.

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