Knowing the atomic weights of Na+ and Cl- are 23 and 35.5, respectively, calculate the density (g/cm^3) of NaCl crystal. Hint: Avogadro’s number N = 6.02 x 10^23 is the number of atoms in one mole (weight of 1 mole = atomic weight in grams)(adsbygoogle = window.adsbygoogle || []).push({});

unit cell is Face centered

unit cell contains a total of 4 Na+ atoms and 4Cl- atoms

unit cell is a cube with length 'a'.

so far I have found the mass of the total unit cell to be

m = 4( 23 + 35.5) = 234g/mol

and now im trying to find volume per mol but I'm not sure if I am doing this right...

I found volume by cubing length 'a' because its a cube. I was wondering if I could avagadros number by the volume and then multiply that with 234g/mol to find the density

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# Homework Help: Unit cell Density Problem

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