Di v Bis

[lilyhoke 2E]

Hi,

I'm confused about when to use di vs bis to indicate two of an atom, and the same for tri. If anyone could clarify the rules I would really appreciate it!

[305878818]

Use "di" and "tri" for simple inorganic compounds indicating two or three atoms, respectively (e.g., dioxide, trioxide). In coordination compounds, employ "bis" and "tris" to specify two or three identical ligands around a central metal atom (e.g., bisulfide, tris(ethylenediamine)cobalt(III)).

[Mackenzie_Kirk]

Hello!
Another way I identify when to dis or tris over di or tri is if the compound already has the name di or tri in the name. Then it would be appropriate to use bis... instead of having di..di..