Question

find out the valency of an element X having atom atomic number 16

Answer 1

Element X has atomic number 16 so  from priodic table we conclude that the element X is Sulphur.

so the electronic configuration of this element sulphur will be given as -
                  1s2 2s2 2p6 3s2 3p4              OR               [Ne] 3s² 3p⁴

from above we conclude that the element has -2 valancy.
Since sulphur only needs 2 electron to complete its octet.

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ROYALJATT

Answer 2

Atomic number -Z- 16
SO, Numbers of protons=16
As atom is electrically neutral so number of protons = number of electrons.
So number of electrons =16
Electronic configuration:
1s22s22p63s23p4
So valence electrons=6
As to attain octet configuration for stability it needs 2 more electrons.
Valency =2
Element is sulphur.