URGENT HELP NEEDED PLZ

[bamteck]

A solid iron cube of side 20mm has a mass of 6.3x10^-2 kg.
One mole of iron atoms has a mass of 5.6x10^-2 kg.

(i) How many iron atoms are there in the cube?
(ii) Hence, find the maximum volume that the iron atom could occupy in the solid state.
(iii) Use your answer to b(i) above to estimate the diameter of an iron atom.

 

[UxaiR]

(i) the Total Mass of the Cube is due to all the Atoms inside , so to calculate iron atoms in the cube we would divide total mass of cube by one Atom of the iron cube
mass of one Atom of iron cube
= 5.6x10^-2 / 6.0221415 x 10^23
= 9.099 x 10^ -26

No of Atoms
= 6.3x10^-2 / 9.099 x 10^ -26
= 6.92 x 10^23


(ii) total volume of cube is 20 x 20 x 20 = 8000 mm^3

And 1 Atom can occupy a volume of
= 8000 / 6.92 x 10^23
1.156 x 10^-20

(iii) since it is a cube divide the total no of atoms by 3 to calculate no of atoms in one side
= 6.92 x 10^23 / 3
= 2.30 x 10^23

diameter = 20 / 2.30 x 10^23
=8.696 x 10^ -23 mm

 

[bamteck]

Thank you very much