Question

In diamond, carbon atom occupies FCC lattice points as well as alternate tetrahedral voids. If edge length of the unit cell is 356 pm, then radius of carbon atom is 

(A) 77.07 pm 

(B) 154.14 pm 

(C) 251.7 pm 

(D) 89 pm

Answer 1

Correct option  (A) 77.07 pm

Explanation:

 Analyzing unit of tetrahedral void 

In the shown fig. of four carbon atoms, there is one more carbon atom which is in tetrahedral void of the group. It is in touch with all other carbon atoms. None of the 4 carbon-atoms touches each other.