CO Paramagnetic/Diamagnetic & Bond Strength

[camboguy]

Question Details:
Is CO paramagnetic or diamagnetic? i put diamagnetic because there are no lone paris is that corrects?

and

If CO gained one election, becoming CO^-, would the bond become weaker or stronger? i believe that the bond would become weaker since there is one lone pari and it makes it an ion and wants to lose the added election, is that correct?

 

[Ygggdrasil]

The best way to answer these questions and check whether you are correct is to draw the molecular orbital diagrams. The diagram would directly show you whether you have any unpaired electrons (unpaired electrons, not lone pairs, make a substance diamagnetic or paramagnetic). Furthermore, the diagram would allow you to calculate the bond order from the number of electrons in bonding and antibonding orbitals, and this would tell you whether the bond order increases or decreases when you add an electron to CO.