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woelen's Achievements


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  1. It's a long time ago that I have posted here. Some of you may remember me from one year ago (or something like that) and the time that I have been very active on this forum, especially in the chemistry and also in the math sections. I can only draw the conclusion from all my reading of the last few months that SFN has become the militant atheists platform, despite the effort of the moderators to make things different. Is this a science forum? I more and more doubt this. I just want to express my sadness on how SFN has developed the last year. Less science, more extreme POV's. The attitude and taste of this makes me sad. You take away the fun of being a scientist for many people. Do you really think YOU have the truth and all those religious people are retarded. I don't expect an answer, I only post this in the hope that some of you will reflect on what they write. The attitude I see over here on SFN does harm to the image of science. I already have met a few people, who were scared away by what they have been reading over here. Not because of scientific contents (which unfortunately is slowly going to a lower level), but because of the arrogant attitude of "we all know what is best for the world, and all those religious persons are poor souls who still did not see the light". What I am writing certainly does not apply to all of you. I especially want to tell this to the moderator team. But I simply could not resist to express my sad feelings which I have after lurking this forum for the past 8 months.
  2. There are paints (waterpaints, used for children's painting on paper), which easily can be rinsed away with water and a brush. These paints should not be confused with water-based permanent paints. The latter are considerably harder to remove. So, be sure to obtain the stuff, used by children.
  3. Look at the place of the central atom in the periodic table. Halogens are at the last row (-1) before the inert gases, sulphur, selenium and tellurium are two rows (-2) before the inert gases, and phosphorus and arsenic are three rows (-3) before the inert gases. Exceptions are nitrate and nitrite, carbonate. These are -1, -2 instead of -3, -4. Also, keep in mind that phosphate has charge -3, but phosphite has charge -2 (you say -3). But this is not an exeption to the 'rule' I gave above. Phosphite only can give up two hydrogens, so the acid H3PO3 is diprotic and not triprotic. Hypophosporous acid is H3PO2, and that only can give up 1 hydrogen ion, so hypophosphite ion is H2PO2(-).
  4. Why not use blue paint?
  5. If any copper sulfate were formed, then it would not stick to the statue for a long time. Copper sulfate is water-soluble. Any rain, or any attempt to clean the statue, would remove the copper sulfate. Adding zinc to the copper sulfate does make copper, but don't expect that to stick to the statue.
  6. But now I have another question. Do you do this, just for fun or for educational purposes, or do you really want to have K4Fe(CN)6. For almost all people in the world, obtaining K4Fe(CN)6 is quite easy, it even is mentioned on eBay every now and then. On the other hand, obtaining KCN is VERY hard (and for good reasons). I know of a few people who do their best to make KCN (or NaCN) from K4Fe(CN)6 and hence I find it funny to read that you want to go the other way around.
  7. What you suggest certainly will make the hexacyanoferrate (II) ion in solution, but you need excess of KCN in solution. Initially, you'll get a precipitate, but on addition of more solution of KCN, this precipitate will dissolve. Adding acid does not seem like a wise idea to me, especially if you are heating as well, this may be extremely dangerous, due to the creation of HCN. The hexacyanoferrate ion is stable, even to moderately concentrated acid, but the free cyanide of the excess KCN definitely will form HCN. If your goal is making prussian blue, then there is no need to isolate the hexacyanoferrate (II). In this case, simply add acid (in a fume hood!) and add an iron (III) salt. The dark blue prussian blue will precipitate from the solution.
  8. The HNO3 will attack the tubing, albeit slowly. But in the long run it will be eaten, and I would certainly not use 90% HNO3 in aluminium apparatus.
  9. All of you know burning, and also even exploding of gas/air mixtures. Burning also is possible in chlorine gas. The following experiment does not require any exotic chemicals and can be carried out at home. http://woelen.scheikunde.net/science/chem/exps/cl2_c2h2/index.html If you do this experiment, please do not scale up, and make the chlorine gas outside or in a fume hood.
  10. Indeed, you don't need to reach escape velocity. The escape velocity is the initial velocity, needed for a passive object without own driving force, to escape earth. E.g. if you shoot a bullet vertically, then you need escape velocity (somewhat more, due to atmospheric hindrance). If an object has its own driving force (e.g. a rocket with fuel), then a lower velocity can be used to escape earth. The driving force just needs to be larger than the graviational pull in the opposite direction.
  11. You want a religion-based forum? In order to do religion bashing over here? Your previous post does not indicate an openminded attitude towards religion and it gives me the impression that you just want to show how superior you (and science) are, relative to religious people (and religion).
  12. Indeed, I agree with YT. I regard this just as a nice curiousity, and it has nothing to do with drugs (chlorobutanol is not even classified as a drug, and it can be purchased without prescription for relieving people from travelling illness). Your initial product also was chloroform, but the smell probably was mixed with an acrid chlorine/hypochlorite smell. The so-called haloform reaction is unique in its property, that only CHCl3 can be formed (or CHBr3 or CHI3 if hypobromite/hypoiodite is used) and not any other halogenated hydrocarbon. So, formation of CH2Cl2 cannot be the case. Search the net for "haloform reaction" and a lot of information pops up. This is quite an interesting reaction on its own. That makes chloral, CH3C(=O)Cl. When you add some water to this, you get chloral hydrate. Chloral has properties, similar to chlorobutanol, it also makes you numb. But it does not have that nice smell. You will also have side reactions, but the main product will be chloral.
  13. Such household items do not exist. If you want Mg-metal, then you have to buy it. Now you have sufficient suggestions for where to look.
  14. You want magnesium without buying it? Then you'll have a hard time. Making it from other (household)items is very hard. Magnesium is not easy to make at all from magnesium salts and it also is not worth the effort. Have a look at eBay. There are quite a few sellers, who sell magnesium ribbon and sometimes also larger chunks of magnesium are offered. Just search for magnesium metal. Finding powdered magnesium will be MUCH harder. Powdered metals are something which officials do not like you to have. Those can be used for making flash powders and in most countries that is regarded a socially less accepted act.
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