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A metal oxide crystallise in a hexagonal...

A metal oxide crystallise in a hexagonal close packed array of oxide ions with two out of every three octahedral holes occupied by metal ions.The formula of metal oxide is

A

`FeO`

B

`Fe_3O_4`

C

`Fe_2O_4`

D

`Fe_3O_5`

Text Solution

Verified by Experts

The correct Answer is:
C
equilateral triangles each with side `a = (6 sqrt3)/(4) a^2`
height of the unit cell(h)=2 x distance
between adjacent layers `= 2 xx sqrt(2/3) a `
Volume of the unit cell= base area x height
`= ( (6 sqrt3)/(4) a^2 ) xx 2 xx sqrt(2/3) a = 3 sqrt2 a^3`
Putting a = 2r , volume ` = 24 sqrt2 r^3`
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NARAYNA-SOLID STATES-EXERCISE-4
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  7. Iron has body centred cubic lattice. If the edge length of the unit ce...

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  8. LiCl has rock salt structure, with an edge length of 6.0Å. If anions ...

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  9. Aluminium crystallizes in a cubic close packed structure. Its metallic...

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  10. In face - centred cubic (fcc) crystal lattice, edge length is 400 pm....

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  11. Ammonium chloride crystallizes in a body-centred cubic lattice with a ...

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  12. First order X-ray reflection (lambda=154pm) is maximum from a set of (...

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  13. The volume of atom present in a face-centred cubic unit cell of a meta...

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  14. Copper crystallises in fcc with a unit cell length of 361 pm. What is ...

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  15. The edge length of a face centred cubic cell of an ionic substance is ...

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  16. Lithium forms body centred cubic structure. The length of the side of ...

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  17. CsClcrystallizes in body centred cubic lattice. If 'a' is its edge len...

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  18. There is a collection of crystalline substances in a hexagonal closed ...

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