How to know when subscripts refer to charges or not [closed]








**Closed**. This question needs [details or clarity](/help/closed-questions). It is not currently accepting answers.
 
 






---








**Want to improve this question?** Add details and clarify the problem by [editing this post](/posts/43628/edit).




Closed 4 years ago.








[Improve this question](/posts/43628/edit) 



My question is very easy. Sometimes to determine to charge of a compound you multiply the charge by the number of ions you have of that element. But sometimes it seems as if you don't do it this way. Example:


* $\ce{Ba(BrO2)NO2} = \ce{Ba^2+ + BrO2^0 + NO2^-}$: Here you multiply the subscript by the charge of 1- in order to balance it
* $\ce{KNaCO3} = \ce{K+ + Na+ CO3^2-} $: here you **don't** multiply the subscript 3 by the charge 2- for it to be balanced.


Could someone please explain the difference? When do you mdo a multiplication and when not?


