The Actinide Series

Give the general electronic configuration of actinides.

Why do actinoids get tarnished in air ?

Give the formula which expresses the general electronic configuration of actinoids.

Write down the electronic configuration of ${\mathrm{Th}}^{4+}$.

Which is the last element in the series of the actinoids? Write the electronic configuration of this element. Comment on the possible oxidation state of this element.

 What are actinoids? Write the names of all the actinoids. 

Actinoid contraction is greater from element to element than lanthanoid contraction. Why ?

What is the maximum oxidation state in actinoids? 

There are $14$ elements in actinoid series. Which of the following elements does not belong to this series?