when is a roman numeral most likely needed in the name of an ionic compound?\nwhen more than one polyatomic…

when is a roman numeral most likely needed in the name of an ionic compound?\nwhen more than one polyatomic ion appears\nwhen the anion is a polyatomic ion\nwhen more than one cation is used in the formula\nwhen the cation is a transition metal
Answer
Brief Explanation:
Roman numerals are used in ionic - compound naming to indicate the charge of transition metal cations, as they can have multiple oxidation states.
Answer:
when the cation is a transition metal