Poly-atomic Formulas and Names


Error message

Warning: Illegal string offset 'theme_pager_link' in cleanpager_theme_registry_alter() (line 338 of /home/yeahchemistry/public_html/sites/all/modules/cleanpager/cleanpager.module).



I would like to say thank you for taking your time to answer my question, in advance.


My quetsion is when you are writing the formula of a poly atomic substance how do you know the charge on one of the symbols. 


For example I am looking at gold (III) Nitrate. 


The steps in my book say to first get the symbols which  are : Au No3

Then it says to add the valences. Based on the periodic table, I see that Au has a valence charge of +1.  

The final answer it gives is Au(NO3)3


I am just unsure of how to go from the names and add the charges in. 


Please so steps. I am desperate. 

The method which you are using is applicable only on the elements of the representative elements of the periodic table.1 and 2 group and then 3,4,5,6,7 group 

Gold is a transition element and icharge on it is decided by the numbers written in roman numerals in the formula so Au3+ 

nitrate is a polyatomic ion and it is compulsory to know some basic polyatomic ions with their charges ...or you should have a good knowledge of making of lewis structures and formal charges 

Nitrate as -1 charge on it 

Au3+   and NO3- ...now make the formula.