Question

A copper atom consists of copper nucles surrounded by 29 electrons. The atomic weight of copper is `63.5 gmol^(-1)`. Let us now take two poeces of copper each weighing 10g. Let one electrof from one piece be transferred to another for every 1000 atom in a piece. ltbRgt (a) Find the magnitude of charge appearing on each piece.
(b) What will be the Coulomb force between the two poeces after the transfer of electrons if they are 10cm apart?

Answer 1

Correct Answer - `15.12C`
Number of atoms in 10g of copperis
`n=(10)/(63.5)xx6xx10^(23)=9.448xx10^(22)`
Number of electrons transferred is
`N=(nxx1)/(1000)=9.448xx10^(19)`
(a) Magnitude of charge appearing on either piece is
`q=Ne=9.448xx10^(19)xx1.6xx10^(-19)=15.12C`
(b) `F=(kq^(2))/(r^(2))=(9xx10^(9)xx(15.12)^(2))/((0.10)^(2))=2.05xx10^(14)N`.