what is wrong writing silver(II) carbonate

Question

my prof asked us why the way she wrote that is wrong. 

Answer 1

When writing the name of ionic salts, you need to write the name of the cation, followed by the name of the anion.

 

In your case, the formula is Ag₂CO₃.

 

This means that

• the cation is Ag⁺ (you have two of them). The name of that cation is silver ion. Silver is an an invariant cation, so you do not need to indicate its charge (+1) as a roman numeral (I).
• the anion is CO₃^2–, which is the carbonate anion.

 

So the name of the compound is simply silver carbonate.

 

Answer 2

It should be Silver (I) Carbonate if the chemical equation is Ag₂Co₃

If you had silver(II) carbonate, the chemical equation would be AgCo₃