Question

Carban and silicon are mainly tetravalent but $Ge,Sn$ and $Pb$ show divalency.

Answer 1

• Carbon (C), Silicon (Si), Geranium (Ge), Stannum (Sn/Tin), and Plumbum (Pb/Lead) are all elements that belong to the p block of the periodic table. They have an electronic configuration of the elements is $n{s}^{2}n{p}^2$.
  
• Of the p-block elements, Ge, Sn, and Pb are known to be divalent most of the time, when compared to C and Si, which are tetravalent most of the time.
  
• This is because Ge, Sn, and Pb have an inert pair effect. The inner s electrons have inertness due to the poor shielding capacity of the outer electrons, which brings down the oxidation state of the elements by 2.The valence p-electrons are readily available for bonding while the s-electrons are attached to the nucleus.
  
• Therefore, the elements with large atomic numbers are divalent and C and Si are tetravalent.