Question

how to write chemical formula of carbon dioxide by criss cross method and also by showing its valiency

Answer 1

Carbon has a valency 4 and oxygen 2 but then how is the formula CO derived?

Hi,

C is 4 and O is 2, so yes, it should be always CO2 and never CO. But this is not the case, CO2 is a covalent compound. But in CO, the electron pairs of Oxygen gets delocalized between C and O, creating a resonance structure.

So without another Oxygen atom, the structure becomes stable as Oxygen shares its lone pair with Carbon.

Answer 2

it's the answer
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