Question

Magnetite, a magnetic oxide of iron used on recording tapes, crystallises with iron atoms occupying 1 8 of the tetrahedral holes and 1 2 of the octahedral holes in a closed packed array of oxides ions. what is the formula of magnetite?

Answer 1

There is Eror in this question in the place of 18 there is 1/8 and in the place of 12 there is 1/2

Fe crystalized in CCP

So,

Fe=1/8*2+1/2*1=3/4, O=1

Formula of the compound= Fe in subscript 3/4 O in subscript 1

                                              =Fe3O4

Answer 2

Answer:fe3o4.

Explanation:    let, number of oxide  =N

   according to question,

                                    no. of iron atom=1/8 of tetrahedral void +

                                                                  1/2 of octahedral void

                                                               =1/8*2N+1/2+N

                                                               =N/4+N/2

                                                                =N+2N/4

                                                                =3N/4

     now,iron:oxide=3N/4:N

                              =3N:4N

                              =3:4

Hence , formula of magnetite=fe304.  (hope it help you)