RyanJ Posted October 24, 2005 Posted October 24, 2005 Does anyone happen to know what the strongest Oxidiation and Reducing agents are? I've heared Fluorine can oxidise water and that there are even agents that can oxidise some of the group 0 elements - how sweet! Also, have a hard time remembering which is which, reducing and oxidation, so am I right in saying this: Oxidation agents: take electrons from an element / compound and reduce themselves. Reducing agents: give electrons too an element / compound and oxidise themselves. Cheers, Ryan Jones
jdurg Posted October 24, 2005 Posted October 24, 2005 Yes, you are correct. An oxidizing agent will take electrons and form a more negatively charged species. An oxidizing agent gets reduced, and a reducing agent gets oxidized. Remember the phrase LEO-GER. Lose Electrons Oxidized, Gain Electrons Reduced. The tricky part is that a reducing agent is easily oxidized, and an oxidizing agent is easily reduced. In terms of pure elements, fluorine is the strongest oxidizing agent and cesium is the strongest reducing agent. (Francium may indeed by a stronger reducing agent, but there has never been enough of it in existance to prove/deny that). PtF6-, I believe, is a VERY strong oxidizing agent and is what was used to oxidize Xenon for the first time. Many alkali metal borohydrides are incredibly potent reducing agents as well. As for what typically encountered chemical is the strongest reducing agent, I'm not sure. (Though I am certain someone will come in here talking about some random species that doesn't exist in a stable solution that is mathematically considered the strongest reducing agent. Unless you can go into your chemistry supply cabinet and pull down a bottle of the stuff, it doesn't count. )
RyanJ Posted October 24, 2005 Author Posted October 24, 2005 Woohoo, I finally got it right Yes, thats the one I was talking about: [math]{PtF_6}^-[/math] - I must be powerful ot be able to oxidise any of the group 0 gasses... So, Fluorine is the strongest oxidant as an element and Cesium (Or Francium) is the most poweful reducing agent. So let the competition commense - who cna find out the most powerful reducing or oxidation agent(s)? Cheers, Ryan Jones
YT2095 Posted October 24, 2005 Posted October 24, 2005 Sodium Amalgam is one of the the most powerfull reducing agents that I know of, and yes it does exist too
RyanJ Posted October 24, 2005 Author Posted October 24, 2005 Sodium Amalgam is one of the the most powerfull reducing agents that I know of, and yes it does exist too Hmm, I have never heared of that one - do you happen to know any of its uses? Cheers, Ryan Jones
jdurg Posted October 24, 2005 Posted October 24, 2005 Sodium Amalgam is one of the the most powerfull reducing agents that I know of, and yes it does exist too Yes indeed. That stuff is INREDIBLY neat too! It's a mixture of sodium and potassium metal that actually forms a liquid at room temperature. Then there's also the sodium/mercury amalgam which is actually not something to mess around with. (Due to the toxicity of the mercury, and the high reactivity of the sodium). Anyway, the Na/K alloy is a liquid at room temperature which quickly develops an oxide coating on it. If you disturb the 'puddle', however, the surface is exposed to the atmosphere and will quickly catch fire and burn quite intensely. VERY potent stuff that can quickly get out of hand since it's in a liquid form.
RyanJ Posted October 24, 2005 Author Posted October 24, 2005 Yes indeed. That stuff is INREDIBLY neat too! It's a mixture of sodium and potassium metal that actually forms a liquid at room temperature. Then there's also the sodium/mercury amalgam which is actually not something to mess around with. (Due to the toxicity of the mercury' date=' and the high reactivity of the sodium). Anyway, the Na/K alloy is a liquid at room temperature which quickly develops an oxide coating on it. If you disturb the 'puddle', however, the surface is exposed to the atmosphere and will quickly catch fire and burn quite intensely. VERY potent stuff that can quickly get out of hand since it's in a liquid form.[/quote'] Sounds like fun... I've never actually heared of this stuff so does it have any actuall uses , industrial or otherwise? Do any other such amalgams exist for other elements from group I? Cheers, Ryan Jones
Borek Posted October 24, 2005 Posted October 24, 2005 I doubt sodium amalgam is stronger than the sodium itself. Much more convenient for use, that's for sure. Best, Borek -- Chemical calculators at www.chembuddy.com pH calculator concentration conversion
jdurg Posted October 24, 2005 Posted October 24, 2005 The sodium amalgam creates a much greater surface area for the sodium metal which results in a much more efficient use of the metal. If you take ten grams of sodium and react it, then take ten grams of sodium placed in a sodium amalgam, the sodium amalgam will react MUCH more rapidly and much more effectively due to the much greater surface area of the amalgam. It's like if you try and ignite a pile of lycopodium powder, nothing much happens. However if you try and ignite finely dispersed lycopodium, a fireball breaks out.
YT2095 Posted October 24, 2005 Posted October 24, 2005 here`s something for the Sodium/Mercury type alloy with regards to your question od Usage: "Sodium amalgam is one of the strongest reducing agents known to science. If you take a metal oxide such as common rust (iron oxide) and you "reduce" it you will end up with metallic iron and oxygen. Sodium amalgam will cause this reaction to occur. It is the absolute best rust remover that you could ever devise. It will also reduce other materials such as zinc, magnesium, manganese, sulfides, etc." lookup also "Charged Mercury" quote taken from: http://www.prospectorsparadise.com/html/mercury.html
RyanJ Posted October 24, 2005 Author Posted October 24, 2005 Hmm, sounds cool. Does the same sort of thing work with Potassium amalgam, Rubidium amalgam etc. if you were to make them? Cheers, Ryan Jones
RyanJ Posted October 24, 2005 Author Posted October 24, 2005 I should imagine so, yes I see I guess the amalgam would become a stronger reducing agent preportionaly to the reactivity of the metal? So Cesium amalgam would be a better reducing agent than say sodium amalgam? Cheers, Ryan Jones
YT2095 Posted October 24, 2005 Posted October 24, 2005 actualy I`de recon Lithium Amalgam would be a little better, as it`s electo-motive potential is alot higher than the others, but then it all depends on the application. why use a shotgun when a fly swatter will do the job just as well
woelen Posted October 24, 2005 Posted October 24, 2005 Using electrolysis, you can make reductors and oxidizers as strong as you like. Fluorine is the strongest chemical oxidizer known and cesium (probably) is the strongest chemical reductor known, but by means of electrolysis even stronger oxidizing and reducing conditions can be created. Redox reactions can be described by means of half-reactions, e.g. F2 + 2e ---> 2F(-) To such redox reactions, a potential is associated. For the reaction, mentioned above, a potential of approximately 3 volts needs to be created. If you electrolyse KF, then for the reduction of K(+) ions to K-metal also some potential is needed (of opposite sign). The total potential needed is somewhere around 5 or 6 volts (I'm too lazy too look up the potential for K(+) + e ---> K ). Usually some extra potential is needed, due to resistive losses and due to an effect called overpotential, which requires a few tenths of additional voltage for a reaction to proceed at an acceptable rate. As you can see, with a voltage of e.g. 10 Volts you have an increadibly strong reductor/oxidizer pair at the cathode and anode. Using such a pair, one can make cesium metal and fluorine gas (provided the correct equipment is used and the reaction products are not allowed to react with material in their neighbourhood). The strongest oxidizer, which I have at home and which is readily available is sodium persulfate, potassium persulfate and ammonium persulfate. The redox potential for the reactoin S2O8(2-) + 2e --> SO4(2-) equals 2.0 volts. This oxidizer is capable of oxidizing Ag(+) to Ag(3+), Mn(2+) to MnO4(2-) and Cr(3+) to CrO4(2-).
RyanJ Posted October 24, 2005 Author Posted October 24, 2005 Ah, right - I see. So electrolysis produces the strongest aqueous reducers / oxidisers Thanks both! Cheers, Ryan Jones
jdurg Posted October 24, 2005 Posted October 24, 2005 Using electrolysis' date=' you can make reductors and oxidizers as strong as you like. Fluorine is the strongest [i']chemical [/i]oxidizer known and cesium (probably) is the strongest chemical reductor known, but by means of electrolysis even stronger oxidizing and reducing conditions can be created. Redox reactions can be described by means of half-reactions, e.g. F2 + 2e ---> 2F(-) To such redox reactions, a potential is associated. For the reaction, mentioned above, a potential of approximately 3 volts needs to be created. If you electrolyse KF, then for the reduction of K(+) ions to K-metal also some potential is needed (of opposite sign). The total potential needed is somewhere around 5 or 6 volts (I'm too lazy too look up the potential for K(+) + e ---> K ). Usually some extra potential is needed, due to resistive losses and due to an effect called overpotential, which requires a few tenths of additional voltage for a reaction to proceed at an acceptable rate. As you can see, with a voltage of e.g. 10 Volts you have an increadibly strong reductor/oxidizer pair at the cathode and anode. Using such a pair, one can make cesium metal and fluorine gas (provided the correct equipment is used and the reaction products are not allowed to react with material in their neighbourhood). The strongest oxidizer, which I have at home and which is readily available is sodium persulfate, potassium persulfate and ammonium persulfate. The redox potential for the reactoin S2O8(2-) + 2e --> SO4(2-) equals 2.0 volts. This oxidizer is capable of oxidizing Ag(+) to Ag(3+), Mn(2+) to MnO4(2-) and Cr(3+) to CrO4(2-). Typically when someone asks what the strongest oxidizing agent is, however, they aren't asking about an electrolysis apparatus. You can't go onto your chemical supply shelf and pull a bottle of electrolysis out and mix that with another reagent and suddenly have the reaction occur. With fluorine, chlorine, oxygen, etc. you can do just that.
YT2095 Posted October 24, 2005 Posted October 24, 2005 true as that may be, it doesn`t hurt to learn a little Something along the way. and he did mention the R-Persuphates that are readily available in almost any chemist or supermarket
jdurg Posted October 24, 2005 Posted October 24, 2005 I know. I'm just being super anal-retentive today. I mean, if you really wanted to get down to it, a plasma of lithium nuclei would make an INCREDIBLY potent oxidizer because it would want to take electrons from just about everything. (Since it's just a bunch of naked nuclei).
insane_alien Posted October 24, 2005 Posted October 24, 2005 LEO-GER ? never heard that one. i use OIL-RIG oxidation is loss - reduction is gain
RyanJ Posted October 24, 2005 Author Posted October 24, 2005 LEO-GER ? never heard that one. i use OIL-RIG oxidation is loss - reduction is gain Same here but the LEO-GER seems like its worth learning too Cheers, Ryan Jones
jdurg Posted October 24, 2005 Posted October 24, 2005 I remember learning the OIL-RIG one as well. Then there's the AN-OX, RED-CAT for remembering what happens at the anode and what happens at the cathode.
Borek Posted October 24, 2005 Posted October 24, 2005 The sodium amalgam creates a much greater surface area for the sodium metal which results in a much more efficient use of the metal. 1. At first the reaction can be pretty fast, but later it will be diffusion controlled (sodium must get to the mercury surface), so the large area effect will be lost. 2. Speed of the reaction will be also modified by other factors. IIRC sodium amalgam reacts much slower with water than one may expect, due to high overpotential of hydrogen evolution on the mercury surface. You may speed up the reaction inserting carbon electrode into amalgam. 3. Half potential of the reaction will not change much, so whether it is pure sodium or sodium in mercury, its strength as reductor is probably about the same. Best, Borek -- Chemical calculators at www.chembuddy.com pH calculator concentration conversion
RyanJ Posted October 25, 2005 Author Posted October 25, 2005 I'd like to see an oxidation agent strong enough to be able to oxadise Helium and thus allow compounds of Helium to be made - does anyone happen to know if one does exist? I guess not ebcase there are no Helium compounds... Cheers, Ryan Jones
MPSchofield Posted May 19, 2014 Posted May 19, 2014 A very strong oxidising agent is Krypton Difluorode, stronger than F2 at around 3.5V but the strongest is PtF6 at around 4.1 stronger than naked Fluorine atoms
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