Electrostatic force betwen two ions

[Knfoster]

Homework Statement

A. Find the electrostatic force between a Na+ ion and a Cl- ion separated by 0.5 nm.
B. Would the answer change if the sodium ion were replaced by Li+ and the CL ion by Br-?Explain.

Homework Equations

I believe you have to use Coulomb's Law...?
F=k* [(/q1//q2/) divided by (r^2^)]

The Attempt at a Solution

I have several of these to do and I'm not really sure where to even begin. If someone could show me step by step how to do this, I would be really greatful. Thanks!

 

[Matterwave]

Just use coulomb's law. Plug in q1 and q2 and r and you're done!

q1=+1e and q2=-1e where e is the fundamental electric charge (you can just look up the conversion to coulombs). r=.5nm.

 

[Knfoster]

Thank you!