SSC CGL 2019 PYQ — Question 40

_____ is a lanthanide. 

Cerium 

What is lanthanide?                 

• Lanthanides are silvery-white metals. Some of them have a slightly yellow colour.
• The rare earth elements (or rare earth metals) include the elements with atomic numbers 57 through 71.
• All of these elements have one valence electron in the 5d shell. 
• The elements share properties in common with the first element in the group -- lanthanum. 
• The lanthanides are reactive, silver-coloured metals.