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Given that a kg of copper contains 10^25 atoms and that density of copper is about 9000kg/m^3,estimate the diameter of the copper atom

Given that a kg of copper contains 10^25 atoms and that density of copper is about 9000kg/m^3,estimate the diameter of the copper atom

Answers

Masinde

Diameter of the atom can be obtained from the volume.
Since the atom is spherical,the formula 4/3pR^3

First we find the mass of a single atom of copper by
=1kg/10^25atoms
=10^-25kg
But Volume=Mass/Density
=10^-25/9000
=1.1 x 10^29 m3

Since the volume of sphere=4/3pR^3
Therefore, (4/3) X 3.142 X R^3=1.1 X 10^-29 m3
R^3=1.1 X 10^-29/4.18933
=2.6257 X 10^-30
Finding the cuberoot of the answer above,we get the radius of the atom in meters
=1.37958 X 10^-10 M
Therefore the diameter will be, 2 X 1.37958 X 10^-10
=2.7592 X 10^-10 M
Converting into the units for atomic radii,
=(2.7592 X 10^-10)/(1.0 X 10^-10)
=2.7592Å
Mr Masinde answered the question on April 25, 2018 at 07:39

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