Advertisements
Advertisements
Question
An element crystallises in a b.c.c lattice with cell edge of 500 pm. The density of the element is 7.5g cm-3. How many atoms are present in 300 g of the element?
Advertisements
Solution
a = 500 pm = 500 x 10-10 cm
z = 2
m = 300 g
`Density(d)=(zM)/(a^2N_A)`
`7.5=(2xxm)/((500)^3xx10^(-30)xx6.02xx10^23)`
`M=(7.5xx(500)^3xx10(-30)xx6.02xx10^23)/2`
`M=282.18 " g/mol"`
`"Molar mass (M)"=("Mass of compound"xxN_A)/"Number of atoms"`
`282.18=(300xx6.02xx10^23)/"Number of atoms"`
Number of atoms = 6.4 x 1023
APPEARS IN
RELATED QUESTIONS
The density of silver having an atomic mass of 107.8 g mol- 1 is 10.8 g cm-3. If the edge length of cubic unit cell is 4.05 × 10- 8
cm, find the number of silver atoms in the unit cell.
( NA = 6.022 × 1023, 1 Å = 10-8 cm)
What is the total number of atoms per unit cell in a face-centered cubic structure?
TiCl has the structure of CsCl. The coordination number of the ions in TiCl is ____________.
A substance forms face-centered cubic crystals. Its density is 1.984 g/cm3 and the length of the edge of the unit cell is 630 pm. Calculate the molar mass in g/mol?
Sodium metal crystallises in a body-centred cubic lattice with a unit cell edge of 4.29 Å. The radius of the sodium atom is approximately ______.
The number of atoms contained in a fcc unit cell of a monoatomic substance is ____________.
Which of the following metal(s) show(s) hexagonal close-packed structure (hcp) and which show face-centered cubic (fcc) structure?
The percentage of empty space in a body centred cubic arrangement is ______.
The coordination number for body center cubic (BCC) system is
A solid is formed by 2 elements P and Q. The element Q forms cubic close packing and atoms of P occupy one-third of tetrahedral voids. The formula of the compound is ______.
