April 12 2012 5 12 /04 /April /2012 18:47
I recently produced a tin oxide thermite.
I took tin metal and dissolved it in hydrochloric acid, then neutralized the resulting solution with sodium bicarbonate. The tin(II) oxychloride was washed with acetic acid, then water, then dried. This light tan powder is then heated. Some combustion occurs, with white tin dioxide smoke being released and red-hot spots appearing and disappearing randomly. However, most of the powder is decomposed to a dark brown color (tin(II) oxide is blue-black but this is not pure). I then grind some magnesium with a file and grind this powder with the tin oxide powder. There is more magnesium than tin(II) oxide. I then grind some magnesium shavings and place them on top of the thermite for ignition. After a few minutes of inaccurate striking, the thermite ignites and does its thing. The thermite reacts noisily like a copper thermite, but without much dispersion. Among the heaps of magnesium oxide ash left behind is some tin metal, which did not fuse together because of the brevity of the reaction.
I really should try making larger thermites. These tiny micro-thermites are so hard to ignite and burn very quickly, without producing any useful products. If I ever make a chromium thermite, I really need to grind much magnesium.
P.S.: I tried grinding magnesium on a grinder to quickly form an ultra-fine powder. The magnesium gets blown all over and hardly any is able to be collected. It is a huge waste of magnesium to try to use such a device.