Sandpit

2012-02-01T10:25:17Z

147.96.5.67:

Fanct ytyest

<math>\overbrace{ 1+2+\cdots+200 }^{5150} </math>

<math>\iint y^2 dy</math>
<math>\iint y^2 rrrr dy</math>
test of 1.16

test fancy

*[[/sandpit2| sand 2]]
test2
Carl es un tontako

test 100

According to scientists, the Sun is pretty big.<ref>E. Miller, The Sun, (New York: Academic Press, 2005), 23-5.</ref>
The Moon, however, is not so big.<ref>R. Smith, "Size of the Moon", Scientific American, 46 (April 1978): 44-6.</ref>
<math> \frac{\partial x}{\partial y}</math>

test 3 [[hard sphere model]]
date test

<math>y=nx^2 + mx+c</math>

:::<math>y=nx^8 + mx^4 +c</math>

<math>y=mx+c</math>
==Notes==
<references/>

[edit]
[[category: Miscellaneous]]

Entropy of ice phases

2009-06-05T16:46:22Z

147.96.5.67: correcting ice rules

==Ice rules==
The '''ice rules''', also known as the ''Bernal-Fowler rules''
<ref>[http://dx.doi.org/10.1063/1.1749327 J. D. Bernal and R. H. Fowler "A Theory of Water and Ionic Solution, with Particular Reference to Hydrogen and Hydroxyl Ions", Journal of Chemical Physics '''1''' pp. 515- (1933)]</ref>,
describe how the [[hydrogen]] atoms are distributed in the [[ice phases| ices]]. Each [[oxygen]] atom has two hydrogen atoms attached
to it, at a distance of approximately 1 ångström, one hydrogen atom resides on each O-O bond. There are
many ways to distribute the protons such that these rules are satisfied, and all are equally probable.
For this reason, the residual [[entropy]] of ice is correctly predicted. The observed residual entropy
was described for the first time using the statistical model for [[ice Ih]] introduced by Linus Pauling
<ref>[http://dx.doi.org/10.1021/ja01315a102 Linus Pauling "The Structure and Entropy of Ice and of Other Crystals with Some Randomness of Atomic Arrangement", Journal of the American Chemical Society '''57''' pp. 2680–2684 (1935)]</ref>.
Pauling suggested a random arrangement of protons. By means
of a simple calculation he showed that the resulting disordered phase requires the addition of
a combinatorial entropy of <math>-Nk_B \ln (3/2)</math> to the theoretical estimate. This finding demonstrated that a crystal
phase such as ice Ih could show full disorder at 0K, which is in contrast to the prediction from the [[Third law of thermodynamics |third principle of thermodynamics]].

==References==
<references/>
'''Related reading'''
*[http://dx.doi.org/10.1063/1.1725363 E. A. DiMarzio and F. H. Stillinger, Jr. "Residual Entropy of Ice", Journal of Chemical Physics '''40''' 1577 (1964)]
*[http://dx.doi.org/10.1063/1.1705058 J. F. Nagle "Lattice Statistics of Hydrogen Bonded Crystals. I. The Residual Entropy of Ice", Journal of Mathematical Physics '''7''' 1484 (1966)]
*[http://dx.doi.org/10.1063/1.452433 Rachel Howe and R. W. Whitworth "The configurational entropy of partially ordered ice", Journal of Chemical Physics '''86''' pp. 6443-6445 (1987)]
*[http://dx.doi.org/10.1063/1.453743 Rachel Howe and R. W. Whitworth "Erratum: The configurational entropy of partially ordered ice <nowiki>[J. Chem. Phys. 86, 6443 (1987)]</nowiki>", Journal of Chemical Physics '''87''' p. 6212 (1987)]
*[http://dx.doi.org/10.1063/1.1808693 Luis G. MacDowell, Eduardo Sanz, Carlos Vega, and José Luis F. Abascal "Combinatorial entropy and phase diagram of partially ordered ice phases", Journal of Chemical Physics '''121''' pp. 10145-10158 (2004)]
*[http://dx.doi.org/10.1063/1.2800002 Bernd A. Berg and Wei Yang "Numerical calculation of the combinatorial entropy of partially ordered ice", Journal of Chemical Physics '''127''' 224502 (2007)]
[[category: water]]

Sandpit

2008-07-01T12:26:07Z

147.96.5.67:

You can make tests here....
'''test'''
''test 2''
[[category: Miscellaneous]]

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Sandpit

Entropy of ice phases

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