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Topic: Calculating surface energy?  (Read 3020 times)

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Offline Sophia7X

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Calculating surface energy?
« on: December 28, 2012, 08:07:17 PM »
Estimate the surface energy of the (110) face of potassium (K) crystals. Express your answer in units of J/cm2. Heat of atomization of potassium is 89540 J/mole.

Solution:


I understand everything except for the 2 bonds/atom * (1.86e-20) part (4th line down, where it says bond energy required for each atom). Why are we multiplying by 2?


How come in the next problem, there is no multiplication by 2 of the energy per bond?

Estimate the surface energy of the (001) face of Rh crystals. Express your answer in units of J/cm2. heat of atomization of Rh is 556.5 kJ/mole.
Entropy happens.

Offline curiouscat

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Re: Calculating surface energy?
« Reply #1 on: December 28, 2012, 10:49:22 PM »
Draw a corresponding unit cell for Rh and show the (001) facet on it.

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