Answer:

Step-by-step explanation:
Hello,
In this case, based on the IUPAC nomenclature, molybdenum (III) refers to the molybdenum with +3 as its oxidation state, that is:

Next, the carbonate comes from the carbonic acid's anion, that is:

Finally, by combining them, one obtains the formula for molybdenum (III) carbonate as shown below:

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