Q8 of 27 Page 1

The electronic configuration of an element ‘X’ is 2,8,6. To which group and period of the modern periodic table do ‘X’ belong. State its valency and justify your answer in each case.

The element belongs to Group 16 and Period 3 of the periodic table. The valency of the element is 2.

Explanation:


1. The electronic configuration of a given element is 2, 8, 6 which means the atomic number of the element can be determined as follows:


Atomic Number of X = 2 + 8 + 6


= 16


2. Since the atomic number of element X is 16, it belongs to Group 16 of the periodic table. The element X contains electrons in three shells, and hence the element belongs to the third period of the periodic table.


3. Valency is the number of electrons required to attain a stable octet of the nearest noble gas configuration. In this, the case the nearest noble gas configuration is 2, 8, 8 and hence the valency of the element X is 2 as it requires only two electrons to attain stable octet.


4. The element X is Sulphur and it belongs to Oxygen family.


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