Five electrons have been removed from each atom to form ions. Find the electrostatic force between two such ions when separated by a distance of `2 Å` in a medium of dielectric constant 4.

Explanation

When five electrons are removed from an atom, then charge on each atom is
`q = 5e = 5 xx 1.6 xx10^(-19)`
`= 8.0 xx 10^(-19) C`
So `q_1 = q_2 = q =8.0 xx10^(-19)C`
`r=2 Å= 2 xx10^(-10) m`
Dielectric constant of the medium = K = 4
`F=1/K1/(4piin_0)(q_1q_2)/(r^2)`
`F=1/4 xx9xx10^9xx((8xx10^(-19))^2)/((2xx10^(-10))^2)`
`=1/4 xx9xx10^9xx((64xx10^(-38)))/((4xx10^(-20)))`
`= 36 xx10^(-9)`
`=3.6 xx10^(-8)N`