At 08:12 PM 2/2/02, Ken Coar wrote: >A stray thought intruded this afternoon.. Why does so >much SF posit chlorine as an energy transport mechanism >parallel to oxygen? Silicon versus carbon I can see, >but chlorine (and hardly anything else, except possibly >methane) versus oxygen? >--
Chlorine is a strong oxidizing agent (steel wool, for example, will burn in chlorine just like in oxygen) and has the same electronegativity (3.5, second only to fluorine) as oxygen. OTOH, (1) the chlorine atom is larger than the oxygen atom, which is also a problem with substituting silicon for carbon (another is that silicon doesn't seem to bond to silicon to form as large and complex structures as carbon does), and (2) I don't know if chlorine-substituted organics have the right balance of stability and reactivity to facilitate life. Or were you asking about Cl-Si-based life? I don't know about that. I have heard some people speculate about life with a fluorosilicone base (a Si-O-Si-O-� backbone with F substituted where H would appear in familiar organics) that perhaps might function in a higher temperature environment than we are accustomed to. Not sure what kind of working fluid would replace water in such an environment, though, as water has a remarkably high-temperature liquid range compared with similar nonmetal hydrides. More recently, some people have suggested that true silicon-based life may come to exist in the form of artificially intelligent computers based on silicon chips . . . -- Ronn! :) God bless America, Land that I love! Stand beside her, and guide her Thru the night with a light from above. From the mountains, to the prairies, To the oceans, white with foam� God bless America! My home, sweet home. -- Irving Berlin (1888-1989)
