Question

What is the co-ordination number of $Cl^-$ in $NaCl$ crystal ?

• A. 8
• B. 6
• C. 4
• D. 3

Answer 1

Answer: (B)

6

Answer 2

In $NaCl, Cl^-$ ions adopts $f.c.c.$ lattice in which $Na^+$ ions are present at all the octahedral sites $\therefore$ Co-ordination number of $Cl^-$ $=$ Co-ordination number of $Na^+ = 6$