The electronic configuration of $Yb^{2+}$ is:

$4f^2$ electronic configuration is found in

Determine the correct $(T)$ and incorrect $(F)$ statements from the following:
$(a)$ The symbol for Lanthanum is $La$.
$(b)$ The name of the element $Lu$ is Lanthanum.
$(c)$ The electronic configuration of $La^{3+}$ and $Ce^{4+}$ contains $4f^0$.

Which electronic configuration is common to all actinoid elements?

The total number of rare-earth elements is

Write the atomic number,name,symbol,and electronic configuration of Actinium and the Actinoids.