Question

Write any four applications of ‘f’-block elements.

Answer 1

Hint:
f-block elements are those in which the last electrons enter the f-orbitals and there are only 28 elements in nature that belong to the f-block and these are known as inner transition elements. Most of the elements of the actinides are radioactive elements.

Complete answer:
We know that there are many elements in the periodic table and they are divided into four parts, i.e, s-block elements, p-block elements, d-block elements, and f-block elements.
f-block elements are those in which the last electrons enter the f-orbitals and there are only 28 elements in nature that belong to the f-block and these are known as inner transition elements. They are lanthanoids and actinoids.
Lanthanides start from atomic number 57 (Lanthanum) to atomic number 71 (Lutetium) while Actinoids start from atomic number 89 (Actinium) to atomic number 103 (Lawrencium).
All the elements are metals and many of the elements of the f-block elements are radioactive elements.
Uses of lanthanides are:
Since the elements have paramagnetic and ferromagnetic properties, their compounds are used in making magnetic and electric devices.
They are used in volumetric analysis like ceric sulfate because it is a well-known oxidizing agent.
Uses of Actinides are:
Thorium is an element of actinide, it is used in atomic reactors and in the treatment of cancer. Its salts are used in making incandescent gas mantles.
Uranium is also an element of actinide, it is used as a nuclear fuel. In the glass industry, textile industry, ceramic industry, its compounds are used as salts.

Note:
The similarity between the lanthanoids and actinoids is, they have a +3 oxidation state in many complexes. Elements of both lanthanoids and actinoids are very reactive and electropositive.