Chapter 6.1, Problem 7SSC

Interpretation Introduction

Interpretation:

The name of the element with chemical behavior similar to silicon (Si) and lead (Pb) and the atomic mass greater than sulphur but less than of cadmium needs to be determined.

Concept introduction:

The modern periodic table is constructed taking the basis of atomic number of elements. Arranging elements in increasing order of atomic numbers causes periodicity of properties. The reason for the periodicity is due to repetition of same electronic configuration of valence shell after a certain definite gap of atomic numbers, such as, 2, 8, 8, 18, 18 and 32.

Answer to Problem 7SSC

The element whose chemical behavior is similar to silicon (Si) and lead (Pb) and atomic mass is greater than sulphur but less than of cadmium is Germanium.

Explanation of Solution

The element to be identified should have chemical behavior similar to silicon (Si) and lead (Pb), that means, the element belongs to the group in which Silicon and lead exists. The group where these two elements present is group 14. Group 14 elements are carbon (C), silicon (Si), germanium (Ge), Tin (Sn) and lead (Pb). Among these elements, the element whose atomic mass is greater than sulphur (32.065 u)are Ge (72.64 u), Sn (117.81 u)and Pb (207.2 u). Last condition to be followed by the element is it has smaller atomic mass than Cadmium. Atomic mass of Cadmium is 112.411 u. So, the element is Germanium.

Conclusion

Elements belong to same group possess similar physical and chemical properties.