I heated a little bit of SiO2 sand with powdered charcoal in a stoiciometrcal 5:1 mass ratio (actually 6:1 to get a bit overdose of carbon) in an
electric arc. The arc is made by a 80A welder with carbon rods and heats the stuff easily to over 2000oC. This results in:
SiO2 + C => Si (l) + CO2 (g)
In the picture (center where the arc occurred) very small globular particles can that be metallic Si ?
The SiO2 "melts" @ 1710oC but then it actually gets a sticky mass in which the Si droplets precipitate, but is this Si ??
blogfast25 - 19-11-2011 at 11:54
Could be: heavily contaminated with SiC of course...
Try and chisel one out of there: Si reacts well with strong alkali, giving hydrogen and silicate... It does look like it.
Oversized photo alert! Try cropping to the part that's most interesting: 75 % of this pic is junk.
[Edited on 19-11-2011 by blogfast25]metalresearcher - 19-11-2011 at 12:55
I put some particles into hot NaOH solution, but no gas escaped. So it is probably SiC. According to http://en.wikipedia.org/wiki/SiC this will form SiC and this substance is produced this way. Adas - 19-11-2011 at 14:48
So next time try to use less carbon.blogfast25 - 20-11-2011 at 06:04
