A copper atom consists of copper nucleus surrounded by `29` electrons. The atomic weight of copper is `63.5mol e^(-1)`. Let us now take two pieces of copper each weighing `10g`. Let us trandfer one elcetron from one piece to another for every `100` atoms in that piece. What will be the Coulomb force between the two pieces after the trandfer of electrons, if they are `1cm` apart? Avogadro number`= 6xx10^(23) mol e^(-1)`, charge on an electron `=-1.6xx10^(-19)C`.

Explanation

Mass fo each piece of copper
`0.01 kg = 10g`
Number of atoms in each piece of copper
`= (6xx10^(23)xx10)/(63.5) = 9.45xx10^(22)`
Number of electrons transferred
`= (1)/(1000) xx 9.45xx10^(22)`
`:.` Charges on the each piece after transfer of electrons,
`q_(1) = q_(2) = +-+ n e = +-+ 9.45xx10^(19)xx1.6xx10^(-19)`
`= +-+ 1.5xx12C`
`r = 0.1m`
`F = (1)/(4pi in_(0)) (q_(1) q_(2))/(r^(2)) = 9xx10^(9) ((15.12)^(2))/((0.1)^(2))`
`2.06xx10^(14)N`