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1:46 AM
@Loong Care to enlarge on why? This is, of course, verging on polywater, which has been shown to be a mythical beast, if there was really nothing in the jar but water, hydrogen and oxygen. One idea that occurred to me was that maybe some contamination got in from the silicone seal (there was some silicone sealant in his electrolysis set-up, too), or from elsewhere in his set-up, leading to some kind of weird polymerization reaction.
It'd presumably have to be quite a small amount, though, which seems on the face of it unlikely to allow such a drastic change, but my chemistry knowledge (BSc level) isn't enough to be sure about that.
(Loong or anybody else who's interested, I mean, of course.)
Leaving aside the question of what it's made from, are there in fact any substances with the properties described? Liquids with a specific gravity of anywhere near 10 seem to be quite rare anyway, although this may only just count as a liquid.
 

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