Advertisements
Advertisements
Question
An atom crystallizes in fcc crystal lattice and has a density of 10 g cm−3 with unit cell edge length of 100 pm. calculate the number of atoms present in 1 g of crystal.
Solution
Given, Density = 10 g cm−3
mass = 1 g
Edge length of unit cell = 100 pm
Volume = `"mass"/"density" = (1 "g")/(10 "g cm"^-3)` = 0.1 cm3
Volume of unit cell = a3
= 100 × 10−10cm3
= 1 × 10−24 cm3
Number of unit cell in 1 g of crystal,
= `"Total volume"/"Volume of unit cell"`
= `(0.1 "cm"^3)/(1 xx 10^-24 "cm"^3)`
The given unit cell is of fcc type. Therefore. it contains 4 atoms.
0.1 × 1024 unit cells will contain 4 × 0.1 × 1024 = 4 × 1023atoms
APPEARS IN
RELATED QUESTIONS
The number of unit cells in 8 gm of an element X (atomic mass 40) which crystallizes in bcc pattern is (NA is the Avogadro number)
The radius of an atom is 300 pm, if it crystallizes in a face centered cubic lattice, the length of the edge of the unit cell is ____________.
If ‘a’ is the length of the side of the cube, the distance between the body centered atom and one corner atom in the cube will be
Potassium has a bcc structure with nearest neighbor distance 4.52 A0. its atomic weight is 39. its density will be
Explain briefly seven types of unit cells.
What is meant by the term “coordination number”?
What is the coordination number of atoms in a bcc structure?
KF crystallizes in fcc structure like sodium chloride. calculate the distance between K+ and F− in KF.
(Given: density of KF is 2.48 g cm−3)
Atoms X and Y form bcc crystalline structure. Atom X is present at the corners of the cube and Y is at the centre of the cube. What is the formula of the compound?
Sodium metal crystallizes in bcc structure with the edge length of the unit cell 4.3 × 10−8 cm. calculate the radius of a sodium atom.