What is the meaning of "NO3 - has three coordination with pi bond involving s,p and d orbitals contributing to the pi bond?" What are hybridisations of N and O in nitrate ion?
In this sentence
The 3- coordination represent the 3 covalent bond formed by NO3- .
And pi bond is ppi ppi type . So p orbital is involved in pi bond formation.
Similar in PO43-.