The element Z=120 would be placed in which family of periodic table ?

Question

Accepted Answer

The element with atomic number Z=120 would be placed in the family of Alkaline earth metals. Here's a detailed explanation supporting this placement:

1. **Justification for Option 3 (Alkaline earth metals):**
   - The periodic table is organized in such a way that elements are placed in groups based on their similar chemical properties. The Alkaline earth metals are located in Group 2 of the periodic table.
   - Elements in Group 2 have two electrons in their outermost shell, which is a characteristic feature of Alkaline earth metals. These elements typically exhibit similar properties such as being shiny, silvery-white, and somewhat reactive at standard temperature and pressure.
   - As we move down the periodic table, new elements are added to the existing groups. Element 120 would follow element 118 (Oganesson, a noble gas) and element 119 (expected to be an Alkali metal). Therefore, element 120 would logically be placed in Group 2, making it an Alkaline earth metal.

2. **Explanation for why other options are incorrect:**
   - **Option 1 (Halogen family):** The Halogen family is located in Group 17 of the periodic table. Elements in this group have seven electrons in their outermost shell and are known for their high reactivity, particularly with Alkali metals. Element 120, with its placement in Group 2, does not fit the characteristics of Halogens.
   - **Option 2 (Alkali metals):** Alkali metals are found in Group 1 of the periodic table and have one electron in their outermost shell. Element 120, being in Group 2, would have two valence electrons, which is inconsistent with the properties of Alkali metals.
   - **Option 4 (Noble gases):** Noble gases are located in Group 18 and are characterized by having a full outer electron shell, making them very stable and unreactive. Element 120, with its expected two valence electrons, does not meet the criteria for being a Noble gas.

In conclusion, based on the organization of the periodic table and the properties of the groups, element Z=120 is correctly placed in the Alkaline earth metals family, supporting Option 3 as the correct answer.