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Roman Numerals

Posted: Sat Nov 18, 2017 10:21 pm
by Mary Becerra 2D
I understand that if the oxidation number of a compound is 2+ (for example) we will use the Roman Numerals (II) when we write out the name. If the oxidation number was negative, is there a way to indicate that when naming a compound? Would there be negative Roman numerals?

Re: Roman Numerals

Posted: Sat Nov 18, 2017 11:22 pm
by Sabrina Dunbar 1I
In terms of naming compounds with transition metals in them, the oxidations of transition metals is never zero (I think) and therefore you would never have a negative Roman numeral. The Roman numeral corresponds to the TW, so as the TM oxidation states are positive, the Roman numerals are also positive.

Re: Roman Numerals

Posted: Sun Nov 19, 2017 1:48 am
by RaviAmin1H
Roman numerals are only correlated with the charge on the cation. The positive charge changes for certain transition metal cations and this is why different elements have different roman numerals. However this is only used for transition metals, which form positive ions or cations. Negative ions with negative oxidation states are usually bound to other atoms and are not the oxidations of the individual atoms. This means that they do not need roman numerals

Re: Roman Numerals

Posted: Sun Nov 19, 2017 3:51 pm
by Jesus Rodriguez 1J
There would not be negative roman numerals because you would only use the roman numerals to describe the different oxidation state of that transition metal.