Question

What are chalcogens?

Answer 1

Chalcogens are found in p-block in the modern periodic table. Some examples of chalcogens can help us understand what chalcogens are. These include polonium (Po), tellurium (Te), selenium (Se), sulfur (S), and oxygen (O).

Complete answer:
In the modern periodic table, the elements in group 16 are known as the oxygen family or chalcogens.
These elements are
Oxygen (O) - atomic number 8
Sulfur (S) - atomic number 16
Selenium (Se) - atomic number 34
Tellurium (Te) - atomic number 52
Polonium (Po) - atomic number 84
Livermorium (Lv) - atomic number 116
The element livermorium (Lv) is chemically uncharacterized and has only ever been created in a laboratory, still, the synthetic element is predicted to be a chalcogen i.e., an element of group 16 of the periodic table. It is extremely radioactive.
Chalcogens have 6 electrons in their outermost shell and hence show similar chemical behavior trends. They do not conduct heat and the stable solid chalcogens are soft.
As one goes down the group
- Electronegativity decreases
- Density increases
- Melting Point increases
- Boiling Point increases
- Atomic and Ionic Radii increases
While in their elemental forms heavier chalcogens are typically toxic, the lighter chalcogens are not only non-toxic but also critical for living organisms.
The naturally occurring chalcogens play a role in biological functions either as a toxin or as a nutrient.

Note:
It should be noted that although the oxygen element is a part of group 16 of the p-block in the periodic table, it is often excluded from the chalcogen of the oxygen family group since its properties vary drastically from the other chalcogens.