• Support PF! Buy your school textbooks, materials and every day products Here!

Naming an Ionic compound from its Formula

  • Thread starter BrainMan
  • Start date
  • #1
279
2

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?
 

Answers and Replies

  • #2
Borek
Mentor
28,443
2,840
This is not an oxoanion.

Besides, it happens that calcite is a (historical) name of mineral - calcium carbonate.
 
  • #3
279
2
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
 
  • #4
Borek
Mentor
28,443
2,840
CaO has no charge.
 
  • #5
279
2
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:
  • #6
Borek
Mentor
28,443
2,840
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.
 
  • #7
279
2
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!
 

Related Threads on Naming an Ionic compound from its Formula

Replies
10
Views
789
  • Last Post
Replies
21
Views
2K
  • Last Post
Replies
9
Views
9K
  • Last Post
Replies
4
Views
740
  • Last Post
Replies
6
Views
8K
Replies
8
Views
28K
Replies
1
Views
2K
  • Last Post
Replies
1
Views
360
  • Last Post
Replies
3
Views
426
  • Last Post
Replies
1
Views
14K
Top