## Calculating Bond Order

104822659
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### Calculating Bond Order

Can you calculate the bond order without the MO diagram?
How do you calculate the bond order of NO3-?

Chem_Mod
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### Re: Calculating Bond Order

You can calculate bond order as long as you know the number of bonding orbital electrons and antibonding orbital electrons.

For something like NO3-, we need to make an MO diagram for a nonlinear molecule, which we will not cover in 14A. However, here is a website demonstrating how to draw an MO diagram for CO2:

http://personal.tcu.edu/thanna/50273/50 ... age020.gif

Using this information, try to solve how you might do an MO diagram for NO3-!

Xinyi_Yan_3L
Posts: 21
Joined: Wed Sep 21, 2016 2:56 pm

### Re: Calculating Bond Order

Basically you can calculate the bond order by counting the bonds, with the help of the lewis structure. For example, O2 has a double bond and has a bond order of 2.
If we draw the lewis structure for NO3-, we may find out that it's a resonance structure with one double bond and two single bonds. So the bond order is 4.