Advertisements
Advertisements
प्रश्न
Gold crystallises into face-centred cubic cells. The edge length of a unit cell is 4.08 × 10–8 cm. Calculate the density of gold. [Molar mass of gold = 197 g mol–1]
When gold crystallizes, it forms face-centred cubic cell. The unit cell edge length is 408 pm. Calculate the density of gold. [Molar mass of gold = 197 g mole–1]
Advertisements
उत्तर
Given:
The edge length (a) of the unit cell = 408 pm = 4.08 × 10–8 cm
M = 197 g mol–1
It crystallises in Face-centred cubic cells.
Density (ρ) = `(nM)/(a^3N_A)`
Where n = Number of particles
For FCC, n = 4
M = Molar Mass
a = Edge length
NA = 6.022 × 1023
ρ = `(197 xx 4)/((4.08 xx 10^-8)^3 xx 6.022 xx 10^23)`
ρ = `788/(67.92 xx 10^-24 xx 6.022 × 10^23)`
ρ = `788/(408.99 xx 10^-1)`
ρ = 1.927 × 10−1
ρ = 19.27 g cm–3
संबंधित प्रश्न
Answer the following in brief.
Calculate the number of atoms in fcc unit cell.
Obtain the relationship between the density of a substance and the edge length of the unit cell.
An element with molar mass 27 g/mol forms a cubic unit cell with edge length of 405 p.m. If the density of the element is 2.7 g/cm3, what is the nature of the cubic unit cell?
Give the percentage of empty space in bcc lattice.
Calculate the number of unit cells in 0.3 g of a species having density of 8.5 g/cm3 and unit cell edge length 3.25 × 10-8 cm.
In bcc unit cell, the edge length (a) and radius of sphere (r) are related to each other by equation:
An element (atomic mass M g/mol) having bcc structure has unit cell edge 400 pm. The density of the element is ____________ g/cm3.
[NA = 6.0 × 1023 atom mol−1)
How many total constituent particles are present in simple cubic unit cell?
The percentage of unoccupied volume in simple cubic cell is ______.
A metal crystallises in bcc unit cell with edge length 'a'. What will be the volume of one atom?
Sodium crystallizes in bcc structure with radius 1.86 × 10−8 cm. What is the length of unit cell of sodium?
An element with density 2.8 g cm−3 forms fcc unit cell having edge length 4 × 10−8 cm. Calculate molar mass of the element.
What is the density of iron crystal which crystallizes in body-centred cubic structure with edge length 287 pm? (At. mass of Fe = 56 amu)
The number of atoms in 100 g of an fcc crystal with density 10 g cm-3 and unit cell edge length 200 pm is equal to ______.
The coordination number of atoms in body-centred cubic structure (bcc) is ______.
An element has a bee structure with unit cell edge length of 288 pm. How many unit cells and number of atoms are present in 200 g of the element?
In face centred cubic unit cell, what is the volume occupied?
Identify unit cell from following having four particles in it
At room temperature, polonium Crystallises in a primitive cubic unit cell. If a = 3.36 Å. Calculate the theoretical density of polonium. [It's atomic weight is 209 g/mol.]
Silver crystallizes in the fcc structure. If the edge length of the unit cell is 400 pm, calculate the density of silver (Atomic mass of Ag = 108).
The correct sequence of the atomic layers in cubic close packing is ______.
The total number of different primitive unit cells is ______.
An element crystallises in fee structure. If molar mass of element is 72.7 g mol -1, the mass of its one unit cell will be ______.
