The Who, What, When, Where and Why of Chemistry
Chemistry is not a world unto itself. It is woven firmly into the fabric of the rest of the world, and various fields, from literature to archeology, thread their way through the chemist's text.
One thing that still stuns me about quantum mechanics is the notion that all molecular motion does not cease at zero degrees Kelvin (despite what you might read in your intro chemistry book). Quantum mechanics tells us that when molecules vibrate, they can only do so at certain frequencies -- or energies. Fascinatingly, the ground state vibrational energies (the lowest vibrational energy state a molecule can be) are not zero. The molecules continue to vibrate, not matter how cold you get the system, you can never freeze out that vibrational energy. Nor is the so-called "zero-point energy" of a molecule negligible. The zero point energy of water is about 7 times as large as the thermal (translational) energy at room temperature). I imagine all these water molecules arrayed in the solid, gently breathing, no matter how much energy you suck out of the system, they keep on vibrating.
Fine, fine, atoms are quantum mechanical objects and I'm willing to believe that the rules are a bit different in this realm, but surely such things are not true of macroscopic object? Physicists Amir Safavi-Naeini and Oskar Painter have shown that objects far larger than atoms exhibit this quantum effect. Watch the video to see how they did it!
While looking for a basic reference on zero point energy to link to, I discovered zero point energy wands...but that's a tale for another day!
No comments:
Post a Comment
Markup Key:
- <b>bold</b> = bold
- <i>italic</i> = italic
- <a href="http://www.fieldofscience.com/">FoS</a> = FoS