Friday, February 26, 2010

Fox 254


This is just a model for a very basic structure in Organic Chemistry. Real molecules are more dynamic than this. Atoms vibrate even at very low temperatures.

3 comments:

  1. Yes, there is an almost-purely-geometric solution for this one. Insert the tetrahedron to the corners of a cube.

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  2. Answer is D.

    By cosine rule to triang. of sides 1, 3/8 & 3/8, cos(mu)= 1- 4/3 = -1/3.

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  3. Sorry.

    Side of tetrahedron a=1 and radius r=sqrt(6)/4, then: a^2 = 2r^2 - 2r^2cos(mu) -> cos(mu) = -1/3.

    Triangle 1,sqrt(3/8),sqrt(3/8).

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