Question

5. Draw the Lewis structures for the nitrate ion. (There are three resonance structures.) Using these Lewis structures describe the bonding in the nitrate ion.

a) What is the geometry about all of the atoms: what is the geometry about the central N atom? What is the electron domain geometry of the oxygen atoms? What are the hybrid orbitals on the N and O atoms in the ion?

b) How many sigma bonds are in this ion? Which orbitals overlap to form these bonds?

c) Describe the pi bonding in this ion. How many electrons are involved in the delocalized system? How can you tell from the resonance forms of the Lewis structure?

Answer 1

Lewis structure represent the bonding and non bonding electron of the structure

a)

geomentry of central atom nitrogen is trigonal planar

oxygen has bent electron domain geomentry

Nitrogen has sp² hydrid orbitals

oxygen has both sp² and sp³ hybrid orbitals

b) nitrate has three sigma bonds, sp2 hydbrid orbitals involved in sigma bonds

c)

nitrate ion has one pi pond which is delocalized in nitrate ions, two electron are involved in the delocalized system

when electron is delocalized from one oxygen to next oxygen, the oxygen having negative charge will have three lone pair of electron, where as double bonded oxygen will have two lone pair of electrons