The octect rule applies well to the first three rows of the periodic table (from Hydrogen to Argon - it also works well with Potassium and Calcium). However, once you start to consider transition metals (or any element starting with Scnadium), orbitals other than s and p need to be taken into account to explain observed reactivity and other properties. The transitions metals such as Iron have access to d orbitals, which can hold up to 10 electrons.
So Iron has 8 electrons in it's valence shell and they are arranged with two electrons in an s orbital and 6 in a d orbital. Because the d orbital can hold up to ten electrons and only has 6, it is not yet full and so iron does not act like a noble gas.
So you sir will be correct. 🙂
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