Advertisements
Advertisements
प्रश्न
Answer the following in brief.
Cesium chloride crystallizes in a cubic unit cell with Cl– ions at the corners and a Cs+ ion in the center of the cube. How many CsCl molecules are there in the unit cell?
उत्तर
Given: Cl– ions are present at the corners of the cube. Cs+ ion is at the center of the cube.
To find: Number of CsCl molecules in the unit cell
Calculation:
i. Cl– ions are present at the 8 corners. The contribution of each corner particle to the unit cell is 1/8. Hence, the number of Cl– ions that belong to the unit cell = 8 × (1/8) = 1
ii. Cs+ ion is at the center of the unit cell. The contribution of a particle at the center to the unit cell is 1. Hence, the number of Cs+ ions that belong to the unit cell = 1
There is one Cl– ion and one Cs+ ion in the unit cell.
Hence, the number of CsCl molecules in the unit cell = 1.
Number of CsCl molecules in the unit cell = 1.
APPEARS IN
संबंधित प्रश्न
Answer the following in one or two sentences.
Which of the three types of packing used by metals makes the most efficient use of space and which makes the least efficient use?
Cu crystallizes in fcc unit cell with edge length of 495 pm. What is the radius of Cu atom?
In ionic crystalline solid atoms of element Y form hcp lattice. The atoms of element X occupy one-third of tetrahedral voids. What is the formula of the compound?
Calculate the packing efficiency for bcc lattice.
In case of hcp structure, how are spheres in first, second and third layers arranged?
A substance crystallizes in fcc structure. The unit cell edge length is 367.8 pm. Calculate the molar mass of the substance if its density is 21.5 g/cm3.
A compound of X and Y crystallizes in ccp structure in which the X atoms occupy the lattice points at the corners of cube and Y atoms occupy the centres of each of the cube faces. The formula of this compound is ____________.
The total volume occupied by particles m simple cubic unit cell is ____________.
The coordination number of each sphere in simple cubic lattice is ____________.
Which of the following contains the highest number of atoms?
The percentage of vacant space of bcc unit cell is ____________.
What is the edge length of fcc type of unit cell having density and atomic mass 6.22 g cm−3 and 60 g respectively?
1 mol of CO2 contains ____________.
Atoms of elements A and B crystallize in hep lattice to form a molecule. Element A occupies 2/3 of tetrahedral voids, the formula of molecule is ______.
What is the percentage of void space in bcc type of in unit cell?
An element crystallizes in a bee lattice with cell edge of 500 pm. The density of the element is 7.5 g cm-3. How many atoms are present in 300 g of metal?
Gold crystallizes in face centred cubic structure. If atomic mass of gold is 197 g mol-1, the mass of unit cell of gold is ______.
AB is an ionic solid. If the ratio of ionic radius of A+ and B- is 0.52, what is the coordination number of B- ?
The relation between the radius of the sphere and the edge length in the body-centred cubic lattice is given by the formula ______.
Calculate packing efficiency in face-centred cubic lattice.
A compound made of elements C and D crystallizes in a fee structure. Atoms of C are present at the corners of the cube. Atoms of D are at the centres of the faces of the cube. What is the formula of the compound?
The packing efficiency of bcc is ______.
A compound has a hep structure. Calculate the number of voids in 0.4 mol of it.
