Answer:
The needed electrons, N = 4 for silicon (Si)
and N = 1 for chlorine (Cl).
Explanation:
Si has atomic number 14 and belongs to group 14 and 3 period.
The electronic configuration of Si is 1s²2s²2p⁶3s²3p².
so, there are 4 electrons in valence shell i.e) third shell (n=3)
so, according to Lewis it needs 4 more electrons to get stability via octet configuration.
Cl has atomic number 17 and belongs to group 17 and 3 period.
The electronic configuration of Cl is 1s²2s²2p⁶3s²3p⁵.
so, there are 7 electrons in valence shell i.e) third shell (n=3)
so, according to Lewis it needs 1 more electrons to get stability via octet configuration.
So, in order to get stability 4 Cl atoms form 4 covalent bonds with 1 Si atom
In a Covalent bond, electrons are shared. so, now both Si and Cl have octet configuration.