Answer:
here is the answer!
Explanation:
Lewis Structure is a very simplified representation of the valence shell electrons in a molecule.
It is used to show how the electrons are arranged around individual atoms in a molecule.
Electrons are shown as "dots" or for bonding electrons as a line between the two atoms.
The goal is to obtain the "best" electron configuration. the octet rule and formal charges need to be satisfied.
1)First determine the total number of valence electrons in the molecule. This will be the sum of the group number a of all atoms plus the charge.
2)Draw a skeletal structure for the molecule which connects all atoms using only single bonds. The central atom will be the one that can form the greatest number of bonds and/or expand its octet. This usually means the atom lower and/or to the right in the Periodic Table
3)Now we need to add lone pairs of electrons. Of the 24 valence electrons available in NO3-, 6 were used to make the skeletal structure. Add lone pairs of electrons on the terminal atoms until their octet is complete or you run out of electrons.
4)If there are remaining electrons they can be used to complete the octet of the central atom. If you have run out of electrons you are required to use lone pairs of electrons from a terminal atom to complete the octet on the central atom by forming multiple bond(s). In this case the N is short 2 electrons so we can use a lone pair from the left most O atom to form a double bond and complete the octet on the N atom.
5) Now you need to determine the FORMAL CHARGES for all of the atoms. The formal charge is calculated by: (group number of atom) - (½ number of bonding electrons) - (number of lone pair electrons)
