Coordination number of "C" in `Be_2C_3` whose structure is correlated with that of `CaF_2` is:

Options

A. 2
B. 4
C. 6
D. 8

Answer

D

Explanation

In `Be_2C_3, Be^(+) ` = In tetrahedral voids

`C_(3)^(2-)` = In fcc arrangement (lattice point a corner + at each face centre)
therefore , coordination number of `Be^(+) = 4`
And coordination number of `C_(3)^(2-) = 8`