Advertisements
Advertisements
प्रश्न
Ferric oxide crystallises in a hexagonal close-packed array of oxide ions with two out of every three octahedral holes occupied by ferric ions. Derive the formula of the ferric oxide.
Advertisements
उत्तर
In hexagonal close packing (hcp), the quantity of octahedral voids is equivalent to the number of constituent particles.
Fe3+ ions occupy two thirds of the octahedral voids in ferric oxide, while O2+ ions form the cubic close-packed structure. If there are nO2−ions in the unit cell, the quantity of Fe3+ ions per unit cell would be `(2 n)/3`.
Hence, formula of ferric oxide = `((2 n)/3)` Fe3+ . (n) O2−
= Fe2nO3n
= Fe2O3
संबंधित प्रश्न
What is the two dimensional coordination number of a molecule in square close packed layer?
A compound is formed by two elements M and N. The element N forms ccp and atoms of M occupy 1/3rdof tetrahedral voids. What is the formula of the compound?
How many lattice points are there in one unit cell of the following lattice?
Face-centred cubic
A cubic solid is made of two elements P and Q. Atoms of Q are at the corners of the cube and P at the body-centre. What is the formula of the compound? What are the coordination numbers of P and Q?
Aluminium crystallises in a cubic close-packed structure. Its metallic radius is 125 pm.
- What is the length of the side of the unit cell?
- How many unit cells are there in 1.00 cm3 of aluminium?
The arrangement ABC ABC.... is referred to as ____________.
In NaCl structure ____________.
With the help of a labelled diagram show that there are four octahedral voids per unit cell in a cubic close packed structure.
The octane number of Iso-octane is
Total no. of voids in 0.5 mole of a compound forming hexagonal closed packed structure are:-
A compound forms hexagonal close-packed structure. What is the total number of voids in 0.5 mol of it? How many of these are tetrahedral voids?
Co-ordination number of sodium ion Na+ in Nacl is:-
The right option for the number of tetrahedral and octahedral voids in the hexagonal primitive unit cell is ______.
The right options for the number of tetrahedral and octahedral voids in the hexagonal primitive unit cells is ______.
The right option for the number of tetrahedral and octahedral voids in hexagonal primitive unit cell is ______.
Element 'B' forms ccp structures and A occupies half of the octahedral voids, while oxygen atoms occupy all the tetrahedral voids. The structure of bimetallic oxide is ______.
What fraction of one edge centred octahedral void lies in one unit cell of FCC?
