(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Calculate the (electrostatic) force between a Ca^{2+}and an O^{2–}ion the centers of which are separated by a distance of 1.25 nm.

2. Relevant equations

I know that:

Coulomb's Law is F = (k q_{1}q_{2})/r^{2}

Attractive Force is F = (k z_{1}e z_{2}e)/r^{2}

where z_{1}and z_{2}are the valence electrons, and e is the charge of an electron.

3. The attempt at a solution

The textbook problem asks for the attractive force, so:

F = [ (9 x 10^{9})(2)(2)(1.6 x 10^{-19})^{2}] / (1.25 x 10^{-9})^{2}

Which is 5.89 x 10^{-10}N

That's the correct answer to theattractiveforce, but the question my instructor has posed is to find theelectrostaticforce.

I'm unsure what the difference between the attractive force and electrostatic force is. Would I just calculate it using Coulomb's Law without taking into account the valence electrons?

Thanks in advance!

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# Homework Help: Calculating the electrostatic force

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