Question

What is the unabbreviated electron configuration of iron?

Answer 1

Of atomic iron, `Z=26`........

Explanation:

`1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)4s^(2)3d^(6)`..........

But hang on......the atomic number `Z` specifies the number of massive, positively-charged nuclear particles. Why should this be equal to the number of electrons in the neutral atom?