Valence Electrons of Lanthanids & Actinids: Get the Answer Here

[mah65]

I want to know what the number of valence electrons of lanthanids and Actinids are.

I have heard several different numbers for them, but please help me about the correct one.

There are 15 elements as Lanthanids & 15 in the group of Actinids. please let me know their exact number of valence electrons, one by one.

thank you very much

 

[Astronuc]

One can find that information oneself at

http://www.webelements.com/lanthanum/atoms.html (see electronic configuration)

La = [Xe] 5d¹.6s²
Ce = [Xe] 4f¹.5d¹.6s²
.
.
.

Ac = [Rn].6d¹.7s²
.
.
.

as well as
http://en.wikipedia.org/wiki/Electronic_configuration#Other_exceptions_to_Madelung.27s_rule

http://en.wikipedia.org/wiki/Lanthanide_contraction
Generally, the lanthanides prefer a +3 state in compounds.

http://en.wikipedia.org/wiki/Actinides

 

[cameronforde]

You say that there are fifteen lanthanides and fifteen actinides, but there are only fourteen. One of the fifteen belongs to the transition metals, but there isn't much agreement on which one. That is, if we look at the fifteen elements La to Lu both La and Lu have a 5d1 electron configuration and are thus candidates to be the first transition element in the third row transition elements (ie under Y). The situation is the same for actinides where Ac and Lr vie for placement in the d-block. If you are interested in how the physical properties compare see the article by Jensen in Journal of Chemical Education 1982 vol 59 p 634-636.