Naming an Ionic compound from its Formula

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Homework Statement


Write the name of the following compound CaO


Homework Equations





The Attempt at a Solution


My book says that for oxoanions the ion with the greatest number of oxygen atoms has the suffix -ate and the one with the least amount of oxygen atoms has the suffix -ite. The books answer was calcium oxide but shouldn't the answer be calcite?
 
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This is not an oxoanion.

Besides, it happens that calcite is a (historical) name of mineral - calcium carbonate.
 
Borek said:
This is not an oxoanion.

Besides, it happens that calcite is a (historical) name of mineral - calcium carbonate.

Why is it not an oxoanion? It has oxygen and a negative charge
 
Borek said:
CaO has no charge.
Ok there is another part of the problem and it is name the following compound PbCrO4. It says the answer is lead(2) chromate. Why would it be this answer because this shouldn't be a oxyanion either? Why wouldn't it be lead chromium oxide?
 
Last edited:
This is a completely different compound - and it is a salt, made of lead(II) (Pb2+) and chromate anion (CrO2-). CrO2- is an oxyanion (and has a charge, which in a compound is neutralized by the opposite charge of lead, yielding PbCrO4).

Note that the first compound contained only one metal (Ca) combined with oxygen, the latter contains two metals (Pb and Cr) - that's a strong hint it is not a simple oxide.
 
Borek said:
This is a completely different compound - and it is a salt, made of lead(II) (Pb2+) and chromate anion (CrO2-). CrO2- is an oxyanion (and has a charge, which in a compound is neutralized by the opposite charge of lead, yielding PbCrO4).

Note that the first compound contained only one metal (Ca) combined with oxygen, the latter contains two metals (Pb and Cr) - that's a strong hint it is not a simple oxide.

Ok I see thanks!