C and Si are almost alwaystetravalent but Ge, Sn and Pb show divalency

1.	C and Si are almost alwaystetravalent but Ge, Sn and Pb show divalency. Why ?
Answer» Solution :Among the elements of group 14, CARBON does not have d- or f-electrons . Therefore , it does not SHOW inert pair effect. CONSEQUENTLY, it shows an oxidationstate of`+4`due to the presenceof two electrons in the s- andtwo electronsin the p-orbitalof thevalenceshell. In contrast , all other elements from GE to Pb containeither dor both d- and f-electron increases, the inertpair effect becomesmore and more prominent. In other words,as we move dow the group from Ge to Pb, the stability of +2 oxidation stateincreases whilethat of `+4` oxidationstate decreases.Therefore , the tendencyof Ge, Sn and Pb to EXHIBIT +2 oxidation state increases with increasing atomic number in group 14.

Discussion