🎁Question 1-Name the members of the lanthanoid series which exhibit +4 oxidation states? (Chemistry 2018-19 AMU +2)

$Ce(Z=58),Pr(Z=59),Nd(Z=60),Tb(Z=65)$ and $Dy(Z=66)$ shows +4 oxidation state. They acquire electronic configuration closer to $4f$

${}^0$ and $4f^7$. 

Related Question

What is the first member of lanthanide series?

lanthanum

Are lanthanides good conductors?

The resistivities of the lanthanide metals are relatively high, ranging from 29 to 134 μΩ·cm. These values can be compared to a good conductor such as aluminium, which has a resistivity of 2.655 μΩ·cm.

What are lanthanides and actinides called?

The lanthanides and actinides together are sometimes called the inner transition elements.

Why are lanthanides Coloured?  The colour of lanthanide ions is due to the presence of partly filled f orbitals. 

What is the most dangerous element? Plutonium