Chemistry How to compute specific surface energy for cubes of varying sizes?

AI Thread Summary
The discussion focuses on the computation of specific surface energy for cubes of varying sizes, with reported values of 0.548 J/g for 1 µm cubes, 9.131 x 10^19 J/g for 1 nm cubes, and 273.890 J/g for 1 nm radius spheres. Participants question the validity of these calculations, particularly the significant discrepancy between the values for 1 nm cubes and spheres. They emphasize the need for the original poster to share their methodology to assess the accuracy of the results. The conversation highlights the importance of comparing magnitudes in similar systems to identify potential errors. Accurate calculations and clear methodologies are essential for reliable results in surface energy assessments.
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Homework Statement
Compute the specific surface energy in J/g for a 1-gram cube of table salt with an edge of 0.77 cm, when it is split into
(a) 1 µm side cubes
(b) 1 nm side cubes
(c) 1nm radius sphere
Relevant Equations
NaCl: Surface energy, γ = 0.2 J/m^2 ; Edge energy, E = 3 x 10^-11 J/m
I got these values but I wanted to make sure I was doing it the correct way
a) 0.548 J/g for system of 1 µm cubes
b) 9.131 x 10^19 J/g for system of 1 nm cubes
c) 273.890 J/g for system of 1 nm radius spheres
 
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As you haven't shown us the way you're doing it, how can we tell if you're doing it the right way?
But compare the magnitudes of your numbers. Do you really expect 1 nm cubes and 1 nm spheres to be so different? Looks like something's wrong somewhere. Please show your working.
 
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