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CaptainPanic

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Everything posted by CaptainPanic

  1. Citric acid is (I think) the most widely used preservative. If not, at least it is very easy to get. Btw, it is known as "E330" in the European food industry.
  2. A Lawsuit before even trying out the Large Hadron Collider... Imagine the lawsuits and claims they get after they destroy the earth! Hahaha!... oh, wait... Apologies.
  3. I am shocked... I definitely expected this picture here too: source: http://www.telegraph.co.uk/earth/main.jhtml?view=DETAILS&grid=&xml=/earth/2008/01/23/scimars123.xml It is better proof of Martians existing (existing? Man, this guy is not just existing, he's chilling out!), and conveniently looking like human beings (rather than CO2 breathing giant slugs with a million eyes and an appetite for Astronauts)... I think KS42 should include this picture in his arsenal, and then proceed to ignore every argument. p.s. I love alien/UFO discussions. It is so cool that the "proof" always has a resolution that is just too low. and that the strongest argument always is "just look at it!". Gimme more!
  4. Regarding problem 1: You are right when you say that [ce] K+ [/ce] and [ce] SO4^2^- [/ce] are not in the reaction equation because they do nothing. You could put them on both sides of the = sign, but why do that when it is ok to leave them out? Those salts are also in water, but you don't put water on both sides of the equation either. Only the water that is produced, or that reacts away is relevant So you have 15.60 ml of [ce] KMnO4 [/ce] at a concentration of 0.0240 M (that is 0.0240 mol/l). This means you have 0.0003744 mol [ce] KMnO4 [/ce]. The reaction: [ce] 5Fe^2^+ + MnO4^- + 8H^+ = 5Fe^3^+ + Mn^2^+ + 4H2O [/ce] So you know that for every mole of [ce] KMnO4 [/ce] you need 5 moles of [ce] FeSO4 [/ce]. Or, because [ce] K+ [/ce] and [ce] SO4^2^- [/ce] are irrelevant, we can say: for every mole of [ce] MnO4^- [/ce], you need 5 moles of [ce] Fe^2^+ [/ce]. So, you need 5 x 0.0003744 = 0.001872 moles of [ce] Fe^2^+ [/ce]. So, now you know how many [ce] Fe^2^+ [/ce] you need. You also know that for each ion of iron (each [ce] Fe^2^+ [/ce] ) you also need one [ce] SO4^2^- [/ce]. So, you need 0.001872 moles of [ce] FeSO4 [/ce]! The concentration of the solution is unknown, but we know that 20 ml of it is enough. So, the 20 ml contain the 0.001872 moles. This means that the concentration is 0.0936 mol/l. About "moles" I have seen this before: people don't know what a "mole" actually is. It's just a number! A mole is 6.022^23. It's like a "dozen". Just a strange word for a number. Only "mole" is a very large number, because we count molecules, or ions, or atoms with it, and they're very small. You see: the concentration of [ce] Fe^2^+ [/ce] is the same as the concentration of [ce] FeSO4 [/ce] because we count the ions ([ce] Fe^2^+ [/ce]) or in the case of [ce] FeSO4 [/ce] , we count salts [ce] FeSO4 [/ce] . If you drop 12 eggs in a bath, and you also drop 12 melons in then the concentration of eggs is equal to the concentration of melons, if you count them per piece. (Obviously, the concentration in grams / liter is not identical... and this is also true for [ce] Fe^2^+ [/ce] and [ce] FeSO4 [/ce]. The concentration in mol/l is the same, the concentration in g/l is different!) That was a long explanation, perhaps too much. But I had a bit of time to waste.
  5. Baking soda is [ce] NaHCO3 [/ce] and that produces CO2 if mixed with (acidic) water. So that works... but you will have more than 1 drop of water in the balloon. (Don't go for strong acid: it eats your balloon, and possibly your hands too). To get 10 liters of CO2, you need about 17 g CO2 (assuming T = 25 deg C). Therefore, you need about 33 g baking soda. Then, assuming you have water of pH = 1 (that's pretty acidic), you need 4 liters of water. You can reduce that to 400 ml if you go for a solution of pH = 0, but then you'll need to be playing with strong acids, and I don't recommend it because of the poor balloon. You see that it's not so easy to make lots and lots of gas with a very limited amount of water. I think "something more energetic" will destroy your balloon because the reaction will increase the temperature. ( And please don't try to go for air-bag material. It is toxic .
  6. Thanks for the links. I guessed already that there was some scifi-journalist who started the idea of the black hole that eats the earth. There is one thing that still concerns me. The CERN guys seem to use the reasoning: what we do is less powerful/violent than what nature throws at us from space. Earth still exists. Therefore we do safe things. It is not the reasoning I was hoping for. CERN's reasoning is a a workaround-reasoning. "Look, birds can fly, they still exist... therefore, flying is safe... therefore, let's jump off this building", in stead of some calculation which takes aerodynamics and a force-balance into account. (Ok, not my best analogy, but I hope you guys see what I mean. Are we 100% certain that what we're trying at CERN is happening all the time in nature, under the exact same conditions?) - btw, I am merely saying that the CERN website does not seem to give me the info I want. Perhaps it is available, but I haven't found it. p.s. Why are all h [ce] <-> [/ce] e ? Did some joker hack the website, or are the mods having a nice 1-4-2008 joke? - Think I will leave the forum for today and come back tomorrow when this is over. I can't be bothered to read posts when someone deliberately makes typos in every post.
  7. Do you guys have links to more info (I'd prefer something with more authority than wikipedia, if possible)? You guys all seem very confident that everything is very safe... where do the widespread doubts come from then? (And why do we even test it, if we already know what will happen?)
  8. The new Large Hadron Collider is coming online soon. It is said to be able to create micro black holes. I immediately admit that any knowledge I have about micro black holes comes from the main stream media (including wikipedia), and is therefore not very good. So, I read about the Hawking radiation, which states that the speed at which a black hole is emitting matter (the rate at which is loses weight) is inversely proportional to its weight. According to this theory, the micro black holes are harmless, because they will in fact lose all their matter so fast, that it might seem a small explosion. http://en.wikipedia.org/wiki/Micro_black_holes But, I also read that this is still debated. Maybe these black holes don't cease to exist quite so soon: http://en.wikipedia.org/wiki/Large_hadron_collider.'>http://en.wikipedia.org/wiki/Large_hadron_collider. And I also read about the possibility that "strangelets" are created, which can turn other matter also into strangelets, thus catalyzing the destruction of the earth. (http://en.wikipedia.org/wiki/Large_hadron_collider - under "Safety concerns") - In the Netherlands, there are examples of people winning the lottery twice. Can anyone guarantee that no stable black hole is created? I mean, even atomic bombs cannot utterly destroy the earth, there'll always be some microbe who will survive that. But all my knowledge about black holes says that it's the one thing that can in fact destroy everything. Why do we even allow someone to try this experiment, when there is a even a very small chance that a black hole created that can eat the earth? In risk assessment, the risk is defined as: chance of something happening multiplied by its effects. Or did I finally become a victim of the media (who generally try to scare people)?
  9. [ce] CO2 + H2O <-> H2CO3 [/ce] [ce] H2CO3 + H2O <-> HCO3- + H3O+ [/ce] [ce] HCO3- + H2O <-> CO3^2^- + H3O+ [/ce] Note that the [ce]<->[/ce] means it is a reaction that goes both ways: it is an equilibrium. p.s. how do I properly write CO3(2-) with the 2- in superscript? Edit: thanks, YT2095 (post #5) [ ce]CO3^2^- [ /ce] did the job even better.
  10. [ce] H2C=CH2 + Cl2 --> Cl-CH2-CH2-Cl [/ce] In words: Ethylene plus chloride gives 1,2-dichloroethane. Ethylene has 1 double bond. 1,2-Dichloroethane has no double bonds at all. An example of a compound with 2 double bonds is for example CO2. It looks like [ce]O=C=O[/ce]. Notice the two "=" signs that are both a double bond.
  11. You talk about the surface of the terrains... but when you talk about "desert" that is put in the middle of a "jungle", does that also mean that there is plenty of rainfall in the jungle, and just 1 meter across the line no rain falls on the desert? Cos that would mean you need some magic to explain it. (If you're asking for ideas that include magic, you probably chose the wrong forum for the question). ... Because, in a more normal world, the plentiful rainfall on the desert that is dumped in a jungle will mean that the jungle will overgrow the desert in a matter of just a few years. In fact, any kind of terrain except mountains is shaped by the sun and climate. I am not sure about the style of the book, but if you want to backup your fantasy world with some more scientific ideas you should start thinking of explaining not how the desert landed in the jungle, but why the hell it remained desert in such a humid place. (Or if you mention permafrost, why it doesn't melt in the tropics). p.s. on earth there are lots of crazy places already. Think of the Namib desert (a thin but long stretch of desert along the coast of Namibia)... or the Kilimanjaro which supports every climate from tropic to arctic.
  12. Just a thought: Take a second piece of metal, call them both "electrode" , dip both in an electrolyte, apply a voltage and try to dissolve the copper. Opposite of copper production. Theoretically, copper should dissolve equal along all the surface (both in and outside). Alternatively, copper is said to dissolve in nitric acid or sulphuric acid. - not too practical because strong acids are kinda nasty. But I assume that this is the "chemical milling".
  13. First of all, I am no expert... and I don't know much about the effects of this particular protein on bacteria. I've never heard of it. All I can do to help is give another example where a changing concentration changes the metabolic pathway: Yeast in low glucose concentrations, with oxygen present will simply grow and produce only CO2 and water (and lots of new yeast cells). If concentrations of glucose go up a lot, it switches to anaerobic growth, even with plenty of oxygen present. Growth almost completely stops, and ethanol production starts. This is well documented, and it is called the "Crabtree effect". Wikipedia has a small article about it, but I'm sure that if you're interested, more info is available: http://en.wikipedia.org/wiki/Crabtree_effect [edit]...And in addition to what YT2095 says: think of elements that are needed in spore-concentrations (ppm or lower)... many (heavy) metals are vital for life, but toxic in high concentrations.
  14. I think boycotting the sponsors would have an interesting effect. The American economy would be suffering from a Chinese invasion of Tibet. Regardless whether boycotting American companies is a good idea or not, I am afraid I really like a Coca cola every now and then
  15. There's a research about Thermo-acoustic heat pumps... these devices convert heat into acoustics (a step which I actually don't understand)... these acoustic waves (at some massive 170 dB or more) are transported through a pipe and generate a significant pressure fluctuation at the other end. Because compression and expansion of gases go together with warming up and cooling down, a temperature difference is created... result: a heat pump. About the company that is doing research: http://www.ecn.nl/en/eei/r-d-programme/industrial-heat-technology/process-heat/thermoacoustic-heat-pump/ A website which shows how it works (click "principle", and then "start"): http://www.aster-thermoacoustics.com/indexeng.html I think it's mad, and I think it's diabolically cool... and that's why I posted it.
  16. No worries Guess we both just have to wait for more data to finish this discussion (or join the research, and hunt for it ourselves, something which I won't do, sorry...).
  17. Glad to be able to help. There is no need to ease my mind, there is even have a special section for homework help... Asking for help with homework is a very good idea. It's a pity that it is kinda tricky to add chemical formula's (the structural formula's especially) here...
  18. The Netherlands has had one of the warmer winters in decades, suggesting global warming. But the last Easter was very cold. This must mean that global cooling started on the 21st of March 2008.
  19. Could I be correct when I say that the Olympics are still the only event in the World where all nations are invited? Blocking the Olympics is not the only action available to the ordinary world citizen. In fact, I think most people have no say in it. Each individual however can choose to stop buying Chinese products. (But the majority chooses not to, because their products are so cheap). Btw, I agree that the Olympics are a commercial circus, but at least in the Netherlands it is still possible to watch most matches and competitions without breaks for commercials. The only ads you see are the ones on the boards at the side of the field/track/course.
  20. Sounds like a homework question to me... so therefore the forum policy says you don't get a complete answer, but first some hints to get you going. The keyword that you may or may not know is "resonance structure". The aromatic ring in Aniline and the NH2 group interact, and electrons move around a bit, creating (mostly) positive charges on the ring and on the side groups. With this keyword you would probably find the following link anyway, so I might as well give it here: http://en.wikipedia.org/wiki/Electrophilic_aromatic_substitution Remember that nitric acid is H+ and NO3-. About question 2: It is again about resonance structures (strengthening my feeling that we are in fact looking at two homework questions). Read the wiki a bit, and also check your textbook which you most likely have. The real question is: how stable is the aniline and the acetaniline once the additional hydrogen is attached (making it in fact an acid).
  21. Right now we are in space to discover and learn, and not to earn money. The knowledge itself is priceless. The products made in space are worth only a fraction of the costs of every mission, and that will remain the same for decades to come.
  22. The ancient Greeks are said to have stopped their wars ("The Olympic Truce") when it was time to have the Olympic Games... this ensured that the athletes could travel safely. Why would we boycot the Olympics, when ancient tradition calls for a Truce while the Olympics are held? If you want to make a statement to China, stop buying their products. (You can recognise them by the little sentence "Made in China"). It's downright hypocrite to call for a boycot of the games and at the same time spend tens or hundreds of euros to buy Chinese products every month.
  23. Well... I started writing about the steel industry's technology which we cannot apply in space (as I said: lack of fossil fuels). But I then proceeded to brainstorm a bit about possible solutions... and it's not completely impossible to for example get metal from ores with current technology. We just need to apply different existing techniques to tackle the new space-problems. Although I sounded pessimistic, I am a believer I just doubt whether it is worth the investment, when we look at cost vs. the benefits, and compare it to other investments (such as sustainable energy systems)...
  24. Another issue is that the technologies to manufacture raw materials (for example steel mills) run on fossil fuels. These are kinda hard to come by in space. There may be plenty of iron, but our traditional way of processing that is to heat it up in a big fire (I do simplify things here for the sake of the discussion). Even if the metal is not an ore, but in metallic form, it still needs to be melted before it can be processed. We could concentrate the sun using mirrors, but there are some problems with transparent reactors that need to be heated to over 1000 degrees Celcius. It's possible, but expensive. And if iron is an ore, we burn off the oxygen using cokes (carbon). We then make a lot of CO2... and steel. The carbon is not available in space. And neither is the oxygen to make the fires. We could perhaps bring our own fuel and oxygen, and recycle it with solar power (hydrogen and oxygen for combustion, then with solar powered electrolysis it is recycled)... Recycling the carbon needed to remove the oxygen from the ore is also possible: we need massive amounts of greenhouses in space: plants could do the job. (btw, there are also chemical ways to do it). And finally, I think that the processes will need to be re-invented. The weightless environment will mean that about every unit in the factory needs to be re-designed. I think that the first step should be to get some kind of power generator up there... Something like a solar-panel-factory. This should be the start of a factory to build more factories.
  25. I am pretty sure that the biodiesel industry (using palm oil to make diesel) is having quite a big impact on Malaysia.
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