Notes

p = purple background site
pl = plain background site

similarities:
-silicon is common in the universe (like carbon) (p)
-silicon is under the same group (group 14) as carbon --> basic chemistry is similar (p)
-silicates are analogs of carbonates (p, pl)
-silicon chloroform are analogs of chloroform (p)
- "Both elements form long chains, or polymers, in which they alternate with oxygen." (polymers) (p)

why instead of boron & phosphorus?
-boron: "it has one less valence electron than the number of valence orbitals, which makes its chemistry noticeably different from that of carbon." (p)
-boron: "One of the biggest drawbacks to boron as a basis for life it is scarcity." (p)
-phosphorus: "a major stumbling is the poor variety of phosphorus hydrides." (p)
-phosphorus: "much of the phosphorus in the terrestrial lithosphere is in the form of phosphates (particularly the apatite minerals), which are not particularly soluble and require further processing in order to be available to organisms." (p) --> "the abundance of phosphorus in solution (or easily soluble form) is significantly lower than is suggested by the pure value in the lithosphere." (p)
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