Advertisements
Advertisements
प्रश्न
Answer the following in brief.
How are the spheres arranged in first layer of simple cubic close-packed structures? How are the successive layers of spheres placed above this layer?
उत्तर
Simple cubic close-packed structures are obtained by stacking two-dimensional square close-packed layers.
So, the spheres in the first layer are placed adjacent to one another to form two dimensional square close packing (i.e., AAAA type arrangement). All the spheres of the successive layers are placed exactly above the spheres of the lower layers. This results in perfect horizontal and vertical alignment between the spheres of various layers.
APPEARS IN
संबंधित प्रश्न
The density of iron crystal is 8.54-gram cm–3. If the edge length of the unit cell is 2.8 A° and atomic mass is 56 gram mol–1, find the number of atoms in the unit cell. (Given: Avogadro's number = 6.022x1023,1A° = 1x10-8 cm)
Choose the most correct answer.
In crystal lattice formed by bcc unit cell, the void volume is _______.
Answer the following in one or two sentences.
Sketch a tetrahedral void.
How are tetrahedral and octahedral voids formed?
Third layer of spheres is added to second layer so as to form hcp or ccp structure. What is the difference between the addition of third layer to form these hexagonal close-packed structures?
The coordination number of spheres in the hcp lattice in three dimension is ______.
The number of octahedral voids formed in 0.5 mol of a compound forming hcp structure?
A metal crystallizes in bcc lattice with edge length 4.48 Å. The radius of the metal atom is ___________ Å.
The ratio of close-packed atoms to tetrahedral holes in cubic close packing is ____________.
A metallic element crystallises in simple cubic lattice. If edge length of the unit cell is 3Å, with density 8 g/cc, what is the number of unit cells in 100 g of the metal?
(Molar mass of metal = 108 g/mol)
The coordination number of each sphere in bcc lattice is ____________.
In two dimensional AAAA type packing, the coordination number of each sphere is ____________.
The coordination number of Rh in the complex [Rh(NH3)3(SCN)3] is ____________.
Which of the following is CORRECT for the two dimensional arrangement of spheres given below?
Zinc forms hcp structure. What is the number of tetrahedral voids formed in 0.3 mol of it?
In ABCABC type arrangement of spheres, the coordination number of any sphere is __________.
Which of the following has hcp crystal structure?
Zinc forms hcp structure. What is the number of octahedral voids formed in 0.2 mol of it?
A metallic element crystallizes in simple cubic lattice. If edge length of the unit cell is 3Å, with density 8 g/cc, what is the number of unit cells in 108 g of the metal?
(Molar mass of metal = 100 g/mol)
What is the coordination number of cation in ionic compound if the type of hole occupied by cation is octahedral?
Percentages of free space in cubic close-packed structure and in the body-centered packed structure are respectively ______.
Which metal crystallises in a simple cubic structure?
The coordination number of cobalt in the complex [Co(en)2Br2]Cl2 is ______.