Okay, I'm hoping someone here can explain this homework qustion I've got bcause we don't seem to have anything in our notes that covers it, so any help would be great- thanks!(adsbygoogle = window.adsbygoogle || []).push({});

Potassium fluoride (K+F-) is an ionic crytal having density 2.48x10^3 kg/m^3

Assuming that the diameters of the K+ and F- ions are approx equal, then make an estimate of the inyer-nuclear separation between the ions in the crystal. The info we're provided with are the relative atomicmasses of the K and F atoms, what one atomic mass uni equals and what 1eV equals. I'm not wanting an answer here, jsut how I should go about it (hence me not filling in all the details fo the quantities there). I was thinking that using the eqts from the Mie potential we could work it out since the attravtive force and repulsive force would be the same at this equilibrium separation bu it doesn't seem clear as to why I'd have to use all these values at the end of the question. Please help!

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# Homework Help: Internuclear separation between ions in a crystal- please help!

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