Would it be possible for life to be based on silicon instead of carbon?

Question

Silicon has kinda similar chemical properties.

Answer 1

It is pretty unlikely. Si-Si bonds are less than half as strong as C-C bonds. Therefore in order to construct a molecule as complex as RNA/DNA that could reliably transmit genetic information, I believe the temperature would have to be a great deal colder, ruling out water as the solvent. A planet like Saturn's moon Titan might be a suitable place. Liquid ammonia could be an acceptable polar solvent. I disagree with the previous answer (BlueJulie) in that Silicon is far, far more common on the Earth and other rocky planets than is Carbon. Also, Silicon CAN generate chiral molecules, since it has 4 bonding sites (just like Carbon). If one considers "silicone" rather than "silicon" based life, then we are talking Si-O-Si type bonds, which are much more stable and these could exist in water as a solvent. But the variety of possible molecules is probably alot less in this scenario. Basically, all of this would be a longshot at best. Carbon-water life is by far the most likely.

Answer 2

I don't have a ready answer for you, but here are some issues to consider.

In order for silicon-based life to exist, ambient temperatures must be much higher than those tolerated by carbon-based life; otherwise, the chemical reactions in cells simply won't get started. But at those temperatures water is no longer a liquid, so ingesting it (or living in it, for that matter) becomes difficult.

It's possible that the water could remain liquid under such temperatures, but the pressure must be correspondingly high. There is, however, a point on the temperature scale (called the critical point, about 374 degrees centigrade), above which water cannot remain liquid no matter what the pressure is.

Wheter temperatures under critical are warm enough for silicone-based life and whether supercritical water is suitable for silicone-based life as an environment and source of hydration, I simply cannot say.

Answer 3

Probably not, since silicon molecules aren't as stable in chains or ring-forms, and are highly reactive. The largest silicon molecule ever found had only six atoms, where carbon molecules can have tens of thousands. That's one reason why carbon molecules are so much more versatile and can bond in so many large and complex forms.

There is also relatively little silicon in the universe, compared to the amount of carbon.

Silicon molecules also lack "handedness," or chirality, which limits the ability of the molecules to form reactions needed for a living silicon-based system.

Answer 4

I certainly won't say it's impossible, as that would be quite presumptuous, but I will say that such a lifeform would have to operate with completely different biochemistry. Carbon and Silicon are not as chemically similar as you might think. Silicon very rarely bonds in sp2 or sp hybridizations, which means that it doesn't form double and triple bonds with itself. This, in effect, means that Silicon would almost assuredly not form any type of polymeric biomolecule like nucleic acids (DNA, RNA), proteins, or lipids. Carbon is uniquely suited for the formation of these types of molecules.

Answer 5

A virtually infinite number of compounds can be made from carbon. Can the same be said for silicon?

Answer 6

Possibly, but the ambient temperature would have to be much hotter since comparable chemical reactions would not occur swiftly enough to permit life at earth-like temperatures. Which would mean life would have to use some other liquid than water.

Answer 7

well most the women in hollywood are living off silicon

Answer 8

Hey, that sounds like an old Star Trek.

Answer 9

Prepare to be assimilated. Resistance is futile.

Answer 10

It is a very large universe, So I would say it is possible.