Mass of one atom of an element is `6.645 xx 10^(-23)` g. How many mole's of element are there in 0.320 kg?

Explanation

Mass of 1 mole=`6.645xx10^(23)xx6.023xx10^(23)`
=40g=1mole
Number of moles=`("mass")/("atomic mass")`
0.320 kg contaims =`320/40`
=8 mol.