Ok, time for a rant here.
I have noticed a preponderance of people writing the word silicon when referring to the rubbery compound. Now this is not a result of people just mistyping the word, they deliberately spell it that way, so let my meltdown commence.
The term Silicon is an element on the Periodic Elemental Table listed as Si with the atomic number of 14. It is a tetrametalloid and is the 8th most common element based upon mass.
When it comes to pronunciation, the end of the silicon word has what is called a schwa, which is a Hebrew word that essentially means the sound of two vowels combined, or an unstressed or neutral vowel. In the case of silicon, the o at the end of pronounced like a cross between the short sound of an E, an A, and/or a U.
Then there is the rubbery compound called Silicone. Notice the e at the end? Applying the childhood rhyme of "When two vowels go walking, the first one does the talking, and the second one is (silent).", the latter syllable is pronounced cone, like ice cream cone.
Rather than typing it out, I'll just copy and paste that: Silicones (more accurately called polymerized siloxanes or polysiloxanes) are mixed inorganic-organic polymers with the chemical formula [R2SiO]n, where R = organic groups such as methyl, ethyl, and phenyl. These materials consist of an inorganic silicon-oxygen backbone (...-Si-O-Si-O-Si-O-...) with organic side groups attached to the silicon atoms, which are four-coordinate. In some cases organic side groups can be used to link two or more of these -Si-O- backbones together. By varying the -Si-O- chain lengths, side groups, and crosslinking, silicones can be synthesized with a wide variety of properties and compositions. They can vary in consistency from liquid to gel to rubber to hard plastic. The most common siloxane is linear polydimethylsiloxane (PDMS), a silicone oil. The second largest group of silicone materials is based on silicone resins, which are formed by branched and cage-like oligosiloxanes.
So, we do not use o-rings or elastomeric products in diving made from silicon, we use them made of siliconE.
