the edge length of FCC is 508 pm if the radius if the cation is 110 pm the radius of anion isans is 114 pm

Rc+Ra=1/2,which implies that answer will 249 pico metre it can also be find by drawing the cube and filled by a pythagorous theorem which implies answer as 249 pico metre

Dear Student,
Please find below the solution to your problem.

FCC can be rock salt,zinc blende,fluorite or anti-fluorite , but we simply consider it to be rock salt
and hence rc+ra=a/2i.e110+ra=254i.e ra=144 pm.

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