Question

The coordination number of $Z{n}^{2+}$ and $S^{2-}$ ions in the zinc blende ZnS type structure is:
A. 4:4
B. 6:6
C. 8:8
D. 4:8

Answer 1

Hint: For these types of questions you should know what type of unit cell is in a given cation or anion, and find the coordination number.

Complete answer:
According to the question we are given the compound ZnS in which $Z{n}^{2{+}_{{}^{}}}$is a cation and $S^{2-}$ is an anion.
As we know cations are occupied in the voids and anions are present in the spheres.
In zinc blende (ZnS), the sulphide ions are anions and are face centered.
It means it has a coordination number 4 while zinc are cation ions which are present in the tetrahedral voids which are alternate.
We know that the coordination number of zinc is 4 and sulphide ion in ZnS is face centered so its coordination number is also 4.
Thus, the radius ratio rate of the cation to that of anion is 4:4 $Z{n}^{2+}$

Hence, option A is correct.

Note: The compound Zinc sulphide can be described as the organic compound with the chemical formula ZnS. It mainly occurs as the mineral but ZnS is the main compound form of zinc in nature. Although the mineral is usually black because of various impurities, the pure material is of white color, and it is widely used as pigment.