Answer:
Their answer is incorrect because CIO2 is not chlorate. ClO3 is chlorate. ClO2 is chlorite however. Furthermore, it is not copper chlorite. It is copper(I) chlorite because copper or Cu is a transition metal and a transition metal requires a roman numeral. They require a roman numeral because a transition metal doesn't have a specific charge/oxidation number as a cation. A transition metal can have like either a charge of +1, +2, +3, +4. Therefore, the correct answer is Copper(I) Chlorite.
Explanation:
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