[Morlaf]

Uranium has the electron shell structure of: 2, 8, 18, 32, 21, 9, 2
how come wikipedia recons 6 of them a valence electrons??
I was expecting only 2 to be valence electrons..

thanks,
Morlaf

[chenbeier]

You have to consider uranium is in the actinoide group, where f orbitals are filled. You have the 7 s², 6 d¹ and 5 f³ ,what makes in sum 6 valence electrons.