Chemistry Helper 

Helping those who are in need of help with various Chemistry related topics...



Transition Metals

    Transition metals form ions that have multiple charges. Some metals form two different ions, and you must use a roman numeral after the metal to distinguish the charge.

Example: Iron (III) Oxide

Fe+3         O-2

We know that the transition metal has a charge of positive 3, and we should have already known, from past knowledge, that Oxide, or Oxygen, has a charge of negative 2. Fe+3 and O-2. Now we must take the numbers for a walk. Fe+3  O-2 becomes Fe2O3.

Example: Tin (IV) Iodide

Sn+4        I-1

Remember that we do not include the 1, because it is understood to be there, even if we do not write it.

Note: the first element is always a positive!

Roman Numerals 
  • 1 = I
  • 2 = II
  • 3 = III
  • 4 = IV
  • 5 = V
  • 6 = VI
  • 7= VII
  • 8 = VIII
  • 9 = IX
  • 10 = X