Question

Number of unit cell in 4 gram of X atomic mass is equals to 40 which crystallizes in BCC pattern is

Answer 1

Answer : The number of unit cell Number of unit cell in 4 gram of X is, $3.011\times 10^{22}$

Explanation : Given,

Mass of X = 4 g

Atomic mass of X = 40 g

Number of atoms per unit cell for BCC (Z) = 2

First we have to calculate the moles of X.

$\text{Moles of X}=\frac{\text{Mass of X}}{\text{Molar mass of X}}=\frac{4g}{40g/mole}=0.1mole$

Now we have to calculate the number of atoms in X.

As, 1 mole contains $6.022\times 10^{23}$ number of atoms

So, 0.1 mole contains $0.1\times 6.022\times 10^{23}6.022\times 10^{22}$ number of atoms

Now we have to calculate the number of unit cell.

$\text{Number of unit cells}=\frac{6.022\times 10^{22}atoms}{2}=3.011\times 10^{22}atoms$

Therefore, the number of unit cell Number of unit cell in 4 gram of X is, $3.011\times 10^{22}$

Answer 2

Answer:0.1NA/2

Explanation:4g of X=4/40mole = 0.1 mole = 0.1×NA atoms

One bcc unit cell has 2 atoms,

therefore, no. of unit cells in 0.1NA

atoms =0.1NA/2