X-ray studies show that the packing of atoms in a crystal of a metal i...
-3.
To determine the atomic radius and the type of crystal structure, we can use the following steps:
1. Calculate the volume of the unit cell:
The density of the metal can be used to calculate its atomic mass, assuming that each unit cell contains one atom:
density = mass/volume
19.4 g cm-3 = atomic mass/atomic volume
Atomic volume = atomic mass/density
Assuming the atomic mass of the metal is around 50 g/mol (typical for a transition metal), we get:
Atomic volume = 50 g/mol / 19.4 g cm-3
Atomic volume = 2.58 cm3/mol
Since every fourth layer is identical, we can assume that the unit cell contains four layers. Therefore, the volume of the unit cell is:
Unit cell volume = 4 x atomic volume = 4 x 2.58 cm3/mol = 10.32 cm3/mol
2. Calculate the edge length of the unit cell:
Assuming that the unit cell is cubic, we can use the following equation:
Unit cell volume = a3
where a is the edge length of the unit cell. Solving for a, we get:
a = (Unit cell volume)1/3 = (10.32 cm3/mol)1/3 = 2.20 cm
3. Calculate the atomic radius:
Since the metal atoms are packed in layers, we can assume that the atoms touch each other along the edges of the unit cell. Therefore, the atomic radius can be calculated as half of the edge length:
Atomic radius = a/2 = 2.20 cm/2 = 1.10 cm
4. Determine the type of crystal structure:
The fact that every fourth layer is identical suggests that the metal has a body-centered cubic (BCC) crystal structure. In a BCC lattice, every atom is surrounded by eight nearest neighbors, located at the corners of a cube, and there is one additional atom at the center of the cube.
In summary, the metal has an atomic radius of 1.10 cm and a BCC crystal structure.
X-ray studies show that the packing of atoms in a crystal of a metal i...
Every 4th layer is identical to 1st layer that means it is ABCABC ( ccp ) close packing structure .
so its cordination no. will be 12 .
No calculation required for this .