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.
Write the relationship between radius of atom and edge length of fcc unit cell.
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.
Derive the relationship between density of substance, its molar mass, and the unit cell edge length. Explain how you will calculate the number of particles, and a number of unit cells in x g of metal.
The pyranose structure of glucose is ____________.
An element crystallizes in fcc type of unit cell. The volume of one unit cell is 24.99 × 10-24 cm3 and density of the element 7.2 g cm-3, Calculate the number of unit cells in 36 g of pure sample of element?
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)
The percentage of unoccupied volume in simple cubic cell is ______.
If the edge of a body-centred unit cell is 360 pm, what will be the approximate radius of the atom present in it? (in pm)
A metallic element has a cubic lattice with edge length of unit cell 2 Å. Calculate the number of unit cells in 200 g of the metal, if density of metal is 2.5 g cm-3?
Which of the following formulae is used to find edge length of bee unit cell?
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)
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?
A metal has an fcc lattice. The edge length of the unit cell is 404 pm. The density of the metal is 2.72 g cm−3. The molar mass of the metal is ______.
(NA Avogadro's constant = 6.02 × 1023 mol−1)
In face centred cubic unit cell, what is the volume occupied?
Calculate the density of metal with molar mass 56 g mol- 1 that crystallises to form a bcc structure with edge length 288 pm.
An element with molar mass 2.7 × 10-2 kg/mol. Forms a cubic units cell with edge length of 405 pm. If the density is 2.7 × 103 kg/m3. Find the nature of a cubic unit cell.
What is base centred (or end-centred) unit cell?
The correct sequence of the atomic layers in cubic close packing is ______.
The total number of different primitive unit cells is ______.
What would be the empirical formula of a compound having a unit cell containing A ion shared equally at the corner of the cube and B ion on the centre of faces of the cube?
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 ______.
The number of particles present in Face Centred Cubic Unit cell is/are ______.
Which of the following metals exhibits minimum packing efficiency in its cubic system?
Calculate the molar mass of an element having a density of 19.2 g cm−3 if it forms an fcc structure [a3 × NA = 40 cm3 mol−1].
