question_answer

                The pyknometric density of sodium chloride crystal is \[2.165\,\times {{10}^{3}}\,kg{{m}^{-3}}\] while its X-ray density is \[2.178\,\times {{10}^{3}}\,kg\,{{m}^{-3}}\]. The fraction of unoccupied sites in sodium chloride crystal is:                                    

A)                 \[5.96\,\times {{10}^{-1}}\]

B)                 \[5.96\,\times {{10}^{-3}}\]

C)                         5.96                       

D)                 \[5.96\,\times {{10}^{-2}}\]