1.

A compound consisting of the monvalent ions, ` A^(+) , B^(-)` crystallizes in the body -centred cubic lattice. (i) What is the formula of the compound ? (ii) If one of ` A^(+)` ions from the corner is replaced by a monovalent ion `C^(+)`. What would be the simplest formula of the resulting compound ?

Answer» (i) Contribution of ` A^(+)` ions present at the corners to wards unit cell =` 8 xx 1/8 =1`
Contribution of `B^(-)` ion present at the body - centre =1
Ration of ` A^(+) : B^(-)` = 1:1 . Hence , the formula is AB.
(ii) ` A^(+)` ions at the corners = 7. Hence, their contribution towards unit cell = ` 7/8`
` C^(+)` ion at one corner contributes = `1/8`
` B^(-)` ion at the body centre has contribution =1 .
Hence, ratio of A:B :C =` 7/8 : 1/8 :1 = 7: 1 : 8`
Formula will be ` A_(7)BC_(8)`


Discussion

No Comment Found

Related InterviewSolutions