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TWJian

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Posts posted by TWJian

  1. the purpose of Sulpher in many Pyro compounds is to only lower the Activation energy (Heat).

     

    Not nesscary that only.The oxidation of sulphur also acts as an energy source,thereby reducing the external heat needed to activate thermite compound indirectly.(the activation energy remains the same)

  2. I got the chemicals required,but I'm not going to try this since its extremly dangerous.

    Nitrogen triiodide monoamine(NI3.NH2)exist in solution but once it crystalize out, it changes(therefore its more stable in solution,but don't count on it not detonating).

  3. I once tried a 65/35 mixture(by weight of ferric oxide and aluminium before.I used labortary grade chemicals.Owing to a lack of a digital scale,Iused a triple beam 1 instead.I filled it in a flimsy, wide cardboard case( i don't want an explosion),stuck a sparkler inside with some Mg shavings for good measure,then placed it in a sandbox.The mixture ignited with a brilliant flame(i had to turn my eyes away even though i was wearing sunglasses).Sparks flew out.A residue of iron and aluminium oxide,together with some molten silica and ashes was left in the sandbox(surrounded by sand).Btw.I mixed the powder by putting it inside a bottle and shaking it for 15 minutes.

  4. Primarygun,I believe i have posted in one of your threads before.I seem to have a vague memory of it when I just joined.Your question about iron as a magnet seems rather vague...I presume you meant ferromagnetism.Reread my post.I have explained that a good electrolyte speeds up the transfer of electrons.Quote myself:"The enchanced corrosion caused by salts are caused by voltaic mechanism:The ions of a salt provide the electrolyte necessary for completion of the electrical circuit."

     

    I quote the Encyclopedia Britinicca since i'm too lazy to type my explanation:

     

    "Ferromagnetism is a kind of magnetism that is associated with iron, cobalt, nickel, and some alloys or compounds containing one or more of these elements. It also occurs in gadolinium and a few other rare-earth elements. In contrast to other substances, ferromagnetic materials are magnetized easily, and in strong magnetic fields the magnetization approaches a definite limit called saturation. When a field is applied and then removed, the magnetization does not return to its original value—this phenomenon is referred to as hysteresis (q.v.). When heated to a certain temperature called the Curie point (q.v.), which is different for each substance, ferromagnetic materials lose their characteristic properties and cease to be magnetic; however, they become ferromagnetic again on cooling.

     

    The magnetism in ferromagnetic materials is caused by the alignment patterns of their constituent atoms, which act as elementary electromagnets. Ferromagnetism is explained by the concept that some species of atoms possess a magnetic moment—that is, that such an atom itself is an elementary electromagnet produced by the motion of electrons about its nucleus and by the spin of its electrons on their own axes. Below the Curie point, atoms that behave as tiny magnets in ferromagnetic materials spontaneously align themselves. They become oriented in the same direction, so that their magnetic fields reinforce each other.

     

    One requirement of a ferromagnetic material is that its atoms or ions have permanent magnetic moments. The magnetic moment of an atom comes from its electrons, since the nuclear contribution is negligible. Another requirement for ferromagnetism is some kind of interatomic force that keeps the magnetic moments of many atoms parallel to each other. Without such a force the atoms would be disordered by thermal agitation, the moments of neighbouring atoms would neutralize each other, and the large magnetic moment characteristic of ferromagnetic materials would not exist.

     

    There is ample evidence that some atoms or ions have a permanent magnetic moment that may be pictured as a dipole consisting of a positive, or north, pole separated from a negative, or south, pole. In ferromagnets, the large coupling between the atomic magnetic moments leads to some degree of dipole alignment and hence to a net magnetization."

  5. Alright,let me explain.All metals except noble metals are thermodynamically cpable of undergoing air in room temprature.However,oxidation can result in the formation of an isulating,protective oxide layer that prevents futher reaction of the underlying metal.Example,aluminium has a standard oxidation potential of 1.66V.It readily oxidizes but the layer of oxide prevents futher oxidation.Magnesium and stainless steel is similiarly protected.

     

    The corrosion of iron is believed to be electrochemical in nature.A region on the surface of iron acts as an anode where the iron undergo oxidation:

     

    Fe(s)->Fe 2+(aq)+ 2e- Eo ox =0.44V

    (Forgive me for the Eo ox part but i can't write it properly)

     

    The electrons then migrate to another potion of the iron surface(cathode)Oxygen is then reduced:

     

    O2(g) + 4H+(aq)+ 4e- -> 2 H2O(l) Eo ox=1.23V

     

    Notice that H+ takes part in the redution of O2.As the concentration of H+ is lowered(ie:increase in pH),the reduction of O2 become less favorable and vice versa.

     

    The Fe2+ ion is then futher oxidized to Fe3+.The Fe3+ forms the hydrated iron(III) oxide known as rust

     

    4Fe2+(aq) +O2(g) +4H2O(l) +2xH2O(l)* -> 2Fe2O3.xH20(s) + 8H+(aq)

     

    The water becomes acidic.The hydrogen ions futher corrode the iron later.

     

    *Rust is a hydrate of ferric oxide with a variable amount of water of hydration.

     

    Because the cathode is genarally the area with the largest supply of O2,rust often deposits there.(experiment:place an iron nail in water.More rust will form on the part exposed to air)

     

    The enchanced corrosion caused by salts are caused by voltaic mechanism:The ions of a salt provide the electrolyte necessary for completion of the electrical circuit.

     

    The ferrous salt(Fe2+) is green but the Ferric salt(Fe3+) is yellow and brown.The red colour could have been formed from complex compounds with impurities like cyanide(the coordination of Fe3+ causes it to change to a red colour)

     

    here's a link that might help you if these are too complex:

    http://science.howstuffworks.com/question445.htm

  6. There is no such protein as "chlorophyll." Chlorophyll is a FAMILY of proteins' date=' they vary. Not all plants are green, so then by your logic how would they photosynthesize? Different chlorophylls absorb different wavelengths of light. By far the most common are the ones that absorb 680nm and 700nm wavelengths, which are green, but others exist.

    Bacteria, such as cyanobacteria, perform photosynthesis with an entirely different family, the rhodopsins.

     

    Also in the case of chloroplasts, it is important to discuss the endosymbiotic theory. The evidence for this theory suggests that chloroplasts were once free-living organisms that were incorporated into eukaryotic cells. This would account for teh similarity.

     

     

    On respiration, the similarity lies in the efficiency; this is the most efficient system that has evolved for the needs of sentient organisms. This is the result of common ancestors. Same for the circulatory system. You can see a clear line of development in the circulatory system as organisms become more advanced. And of course there are variants in this.[/quote']

     

    Hello?If chlorophyll absorbs green light,then why is it green?it absorbs the red spectrum of visible light and reflects the green ones.

  7. I try to branch off a hydrocarbon chain with ceramics(like cracking) or introduce alkanes into the base chain.Sigh,these compunds are ridicolously complex.This time, i try to heat them indirectly.(takes so long since i can't let them boil or 'boom!')Btw,anyone got any tips on syntesizing Undecane?I also need information on the pheromones secreted by Oecophylla smaragdina(a type of weaver ant,can't find it in the pherobase)

  8. Essentially greek fire could be made with a fuel,a binder, a gelling mixture(which could also be the binder),a reactive metal(Zinc and higher),and a reactive fuel(ie: sulfur)The metal would react with water to produce heat,which would ignite the sulfur,then ugniting the entire mixture.

  9. sigh.Headaches to syntesize those pheromones.Blown 2 testubes(I had to cork them up to prevent the chemicals from evaporating) .Any ideas anyone to extract the pheromones from the ants?Currently I'm working on the weaver ant.

  10. Thanks guys. So I presume that strategy is the overall plan for doing something(1st use is in war since strategy means general's plan in Greek) while tactics is the skill and

    manoeuvres executed in acheiving that goal or plan,right?

  11. I'm curious about the difference between strategy and tactics.What do we mean when we say that someone is good tactican but a bad strategist? Vice versa too. can anyone help me? By the way, can anybody explain the above in chess too?

  12. There are many chemicals that fit your criteria,however,most of them either tarnishes and corrodes metal and are extremly unstable.It will wore out after several tries anyway.Best way to use it is to place it on a projectile.I suggest you forget about the entire alchemist/knight thing with scientific basis and just say the sword is enchanted.

  13. I'm doing a study on ants and the pheromones and i need help on the structure of it.(ie:alkenes,proteins,hormones and such) Can anybody help me?I have to get attention this way since nobody is answering by post.

  14. I'm doing a study on ants and the pheromones and i need help on the structure of it.(ie:alkenes,proteins,hormones and such) Can anybody help me?I have to get attention this way since nobody is answering by post.

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