How to find formula for compounds and naming?

So how would you find the formula for sodium carbonate?





And how would you name this formula compound? Fe2O3

How to find formula for compounds and naming?
use the charges of the ions.





cancel out the charges by finding a common multiple of the + and - charges





Na is 1+


CO3 is 2-





common multiple is 2 (ignore the +/-), so you need 2 Na





Na2CO3





That is Iron(III) oxide





check these webpages on formulas and naming out





Kent






Reply:Sodium = Na+, Carbonate (which is a polyatomic ion) = CO3^2-





Since the sum of the oxidation numbers must be zero, we need two sodium atoms for one carbonate.





Na2CO3





Fe2O3 is iron (III) oxide





The iron has an oxidation number of +3 and we name metal-nonmetal compounds using the Stock system. The Stock system is named in honor of Alfred Stock, its inventor. In the Stock system, when a metal has more than one possible oxidation number, we include a Roman numeral to indicate its oxidation number.