Potassium crystallizes in a body centred cubic lattice. Calculate the number of unit cells in 1g of potassium. Atomic mass of potassium = `39mu`.

Explanation

Number of atoms in unit cell =2
39g of potassium contains number· of atoms= `6.023xx10^(23)`
lg of potassium contains .number of atoms `=(6.023xx10^(23))/39`
2 atoms present in number ofunit cell.=1 Unit
`(6.023xx10^(23))/39` atoms present in·number of unit cell= `1/2xx(6.023xx10^(23))/39=7.7xx10^(21)` unit cells