atoms and molecules

[muskan]

I am a ninth class student. Our teacher explained the topic of molecules in the class. CO₂ Molecule is stable and CO₃ is charged. But why CO is stable? please explain.

[Country Boy]

What does "stable" ​mean here?

[muskan]

it has no charge

[Country Boy]

If you really mean "charge" and not "change", then count up the number of protons and electrons in the carbon and oxygen ions.

[OldChemE]

Carbon has the capability to form bonds using multiple numbers of electrons. it can form single, double, and even triple bonds that are stable and have no charge. This allows CO2 and CO. The problem with CO3 is that there are too many available electrons in three oxygen atoms for Carbon to form a neutral bond.

 

I don't have my chemistry books handy (someone who does can clean up my mistakes on this), but if memory serves correctly: In the case of CO, Carbon can contribute 2 electrons to the bond, and oxygen 4, making a triple bond. Thus, The carbon atom (which has 4 electrons) sees 6 in the bond plus its other two making 8, which satisfies the octet rule. Oxygen, having 6 electrons, sees its two plus the 4 it shares and the two from the carbon atom for a total of 8, which also fits the octet rule ( :C:::0: ). This is stable with no net charge. In CO2, we have ::0::C::0::, where Carbon shares two electrons with each oxygen atom, and each oxygen atom shares two with the carbon. All the atoms still see 8 electrons, which satisfies the octet rule. There just simply isn't any combination like this that works for CO3

Edited March 3, 2017 by OldChemE