Question

What do you mean by Lanthanide concentration ?

Answer 1

heya @user
here is your answer

_____________________________

==> The steady decrease in atomic and ionic radii from left to right in Lanthanide series is called them tonight concentration.

⭕ As we move from left to right in Lanthanide series, 4-f electron are added one at each step. The mutual screening effect of f-electrons is very little due to the complicated shape of orbitals. then the nuclear charges, however increases by 1 at each step. Hence inward pull increases.

⭕ This cause concentration.

____________________________

hope helped !!

Answer 2

The lanthanide contraction is the greater-than-expected decrease in ionic radii of theelements in the lanthanide series from atomic number 57, lanthanum, to 71, lutetium, which results in smaller than otherwise expected ionic radii for the subsequent elements starting with 72, hafnium.The term was coined by the Norwegian geochemist Victor Goldschmidt in his series "Geochemische Verteilungsgesetze der Elemente".


Hope this will help you.

Please mark it as the brainliest.