Question

5.
What is the volume of a face centred cubic unit
cell, when its density is 2.0 g cm-3 and the molar
mass of the substance is 60.22 g mol-??
(1) 4 x 10-22 cm
(2) 2 x 10-22 cm² Dam
(3) 44 x 10-22 cm² 2 - 60.22
(4) 22 * 10-22 cm3
molas​

Answer 1

Answer:

Explanation:

Given What is the volume of a face centred cubic unit

cell, when its density is 2.0 g cm-3 and the molar

mass of the substance is 60.22 g mol-??

We know that this is a face centred cubic (fcc) structure, so Z will be = 4

Molar mass of the substance = 60.22 g / mol

Density = 2 g cm^-3

Volume of unit cell a^3 = molar mass x Z / density x Na

                                       = 60.22 x 4 / 2 x 6.022 x 10^23

                         = 20 x 10 ^-23 cm^3

Answer 2

Answer:

Volume of a Face Centred Cubic (FCC) Unit Cell is 2 x 10⁻²² cm³

Explanation:

Given ::

1. It is a FCC Unit Cell.

2. Density => 2.0 g cm⁻³

3. Mass of substance => 60.22 g mol⁻¹

Now, we know that for FCC ,

Z = 4 and Z is the no. of atoms present per unit cell or formula units.

Molar Mass = 60.23 gram

Volume of unit cell => a³ = ( Molar Mass * Z ) / ( Density * Nₐ )

a³ = ( 60.23 * 4 ) / ( 2 * 6.022 * 10²³ )

a³ = ( 60.23 * 2 ) / ( 6.022 * 10²³ )

a³ = ( 10.001 * 2 ) / 10²³

a³ = 20.001 * 10⁻²³ cm³

a³ = 2 x 10⁻²² cm³

Here,

Nₐ = Avogadro Number = 6.022 * 10²³