Lanthanoid Flashcards
What is the common electronic configuration of atoms in these elements?
6s²
This configuration is characteristic of certain elements, particularly lanthanoids.
What variable occupancy is noted in the electronic configuration of these elements?
4f level
The occupancy of the 4f level varies among the elements.
What is the most stable oxidation state of all the lanthanoids?
Tripositive ions
This oxidation state is commonly observed in lanthanoid chemistry.
What is the electronic configuration of tripositive ions in lanthanoids?
4fⁿ (n = 1 to 14 with increasing atomic number)
This indicates the range of f-electrons present in tripositive lanthanoid ions.
What is the lanthanoid contraction?
The overall decrease in atomic and ionic radii from lanthanum to lutetium
What feature does the lanthanoid contraction impact?
The chemistry of the third transition series of the elements
How does the decrease in atomic radii of lanthanoids compare to M3+ ions?
It is not quite regular as it is in M3+ ions
What causes the lanthanoid contraction?
Imperfect shielding of one electron by another in the same sub-shell
How does the shielding of 4f electrons compare to d electrons?
The shielding of one 4f electron by another is less than that of d electrons
What happens to atomic sizes as atomic number increases in lanthanoids?
There is a fairly regular decrease in sizes
True or False: The lanthanoid contraction is a regular feature observed in all elements.
False
Fill in the blank: The lanthanoid contraction occurs from _______ to lutetium.
lanthanum
