|position in periodic table|important points and chemical reaction of lanthanoids

Given the chemical properties of lanthanoides.

What is the importance of the chemical reaction?

Explain the position of actinoids in the periodic table. What is the action of sulphur on lanthanoids ? Calculate the magnetic moment of divalent ion in aqueous solution it its atomic number is 24.

What are the important characteristics of chemical reactions?

what are the important characteristics of chemical reactions?

According to Mendeleev's periodic table , the physical and chemical properties of elements are periodic function of their __________

Predict the position of an element with atomic number 55 in the periodic table and explain the chemical behaviour of tha element.