Applied Chemistry

Hello all, I was wondering whether striking a match is endothermic or exothermic. This seems quite straight forward as striking a match releases heat, which is obviously exothermic. However, the process of igniting the match requires heat in itself, so I was wondering since the reaction required heat, would it be endothermic instead? I read from a post somewhere that for a reaction to be endothermic, heat is absorbed for the reaction to occur. Since heat is required for the initial ignition of the match, wouldn't that be an endothermic reaction? As well, is the bolded statement correct? Thanks

I would like to do a small experiment with calcium chloride. I happen to have some in my possession but it is in the form of little flakes, and I need it to be in a very fine powder form. I'm assuming that the reason for the flakiness lies in its water-absorbing properties. Would I be right in thinking this and, if so, would 'baking' it in the oven on a high temperature dehydrate it enough for it to be finely powdered? Thanks in advance for any replies.

Hello dear friends! Some "chiral" molecules have a right and a left form. http://en.wikipedia.org/wiki/Chiral_resolution http://iupac.org/publications/pac/69/7/1469/pdf/ Biology demands pure enantiomers, especially for drugs, but identical chemical properties make this difficult. Most racemates mix tightly the enantiomers one-to-one when they crystallize, but a few ones separate spontaneously into right and left crystals. To my understanding, such a purified carboxylic acid can separate chiral amines by making salt crystals of differing properties - and purified amines can separate chiral acids. Or such a substance can serve in a chromatography column to separate a prod…

Hi, guys, I know tartaric acid include DL-tartaric acid, L (+)- Tartaric Acid, Anticaking L (+)-Tartaric Acid and D (-)- Tartaric Acid. Do you know the difference between them? Thank you for your help.

Hi, Thanks in advance for answering this question: What are the courses I need to take at undergraduate level to be competitive for a PhD admission in computational chemistry? I know the chemistry courses I need to take. I'm curious about the computer science and math courses I need to take to supplement the application. So far, I have 2 years of calculus (taking calculus 4 this semester), I have 2 semesters of linear algebra, took ordinary differential equations and probability. Planning to take numerical analysis next semester. Question 1: Do I need partial differential equations? What other math courses should I take? Question 2: For computer science…

I was wondering how accurate the measurements of in a typical chemistry lab are of continuous physical quantities like temperature, volume, etc. are in practice. For example, when the temperature of a large body is declared, how does one measure it? Does one calculate the average from all the particles in the body, or what? I hope anyone who is experienced in practice would clarify this doubt. Thank you.

Hello, I'm trying to find something that will work as a pigment in the UVA range. Presumably, that means that this material will reflect in the 350-400 nm range. I have found some materials that will be impractical. If I can trust what I read, one candidate is snow. Great! . . . until my art project is warmer than the melting temp of water. Next candidate: aluminum. Hmmmm. If I make an admixture of aluminum and, say, red paint, the aluminum will be covered (even if it's in powdered form) and therefore not useful as a reflectant. Here's my motivation: Some flowers are bright in the UVA range. If you notice, some flowers sem to "glow" more than their red…

I bought a bunch of half-ripe banana. 6 days later, it still looked not ripe enough to eat, so i waited for another 3 days. It didnt change at all. I finally ran out of my patience and peeled one and took a bite. it tasted nasty and raw. what i did with the rest was to dump it. I guess the sellers put some chemical into it to make it last longer. unfortunately, it destroyed the fruit and it will never become ripe in a natural way. what is that chemical they use ? thanks.

People, Ethylenedinitrillo tetracetic acid disodium salt- I have loads of it but needing a small quantity of the tetrasodium. Can I just add some NaOH to convert it to the tetra somehow, or no way? Say, per gram of disodium, how much NaOH (theoretical 100%. dry) should I need, if doable? Thanks, as always!! Oh- say I cant do this- would the disodium be as efective chelator of metals (Mg, Zn, etc) as the tetra? Opinons appreciated.

People, I use about a liter of high purity nitric/week. This is not ACS, but take ACS, redistill it, thats what Im after. Some applications, I could re-redistill it again, to achieve sub ppb levels of impurities. Man, costs for commercially available trace grade is $$$$ these days. So, anyone know of/experience a practical, lab scale capacity glass distiller? Quartz? kevlar? I understand glass should be OK since nitric doesnt leech out silica or boron, right? Yes, I am starting to look online, but feedback from fellow members is always a plus. Thanks!

Why is the covalent triple bond in diatomic nitrogen so strong? Why is it that this covalent bond is so strong when covalent bonds usually are week?

A simple Q, can pure alkali kill cockroach ? i mean cockroach accidentally eats it and dies. if i am wrong, PL correct me. thanks.

Hey Everyone! I'm interested in doing an undergraduate level research in something to do with nitrosamines in latex. An idea my supervisor gave me is to find out the effects of temperature and other factors that affect nitrosamine formation. Can anyone please help me by suggesting more possibilities that can be researched at my level (undergrad) and i have one year to do the research along with my course work, so that's not really a lot of time. But also this contributes to a major portion of my GPA, so it has to be good enough too.... One other thing, i'm from an asian country, we have rubber trees growing here but we don't have so many high end lab faci…

So I am trying to make a metal casing of animal paws. I am using a clay mold that I created. I have already made a casting of the print using plumbing solder (tin, copper, silver mix) This comes to about $15 a casting using 1/2 lbs of solder wire. I used a charcoal grill to heat up a copper tube to melt the solder then poured it into the cast. To make things cheaper i was wondering what I could add to the liquid metal to be a kind of filler (like using ground up aluminum foil). Or is there something else I could use that is cheaper than $30 / lbs that I would be able to melt in a charcoal fire? Also I melted the bottom of the copper tube the last casting I tried t…

If we have a molecule where an atom has one bond with another atom, does the electronegativity change for those atoms then? If we were to bond one of the atoms once more with another atom, (if we presume it's possible) would the electronegativity then be changed for that atom since it's bonded with another atom already? Or is the electronegativity constant?

My limited knowledge of chemistry suggests that copper sulfate in solution with salt, baking soda, and sodium decahydrate (natron) will precipitate copper hydroxide which would accumulate on the bottom of a very large container. There would be numerous contaminants in this water and solution levels of the copper sulfate would be probably less than .05% but highly variable. The water would be very slightly acidic and turn over rapidly. I believe there is evidence it would turn basalt green. Does this sound right to anyone?

Dear all, Can you suggest how to make NBRubber to biodegradable

Hi ladies and gents, So I have a bit of a conundrum. I'm a restaurateur, doing a series of pop-ups, and am about to do our first Crawfish Boil in a couple of days. But, there's a problem. My chef says the burners the premises we're taking up residence in for the night doesn't have a burner/stove with a high enough temperature output to keep the water at a constant rolling boil even when adding in room temperature ingredients rather than letting the temp of the liquid drop.We're not allowed to bring in any other equipment or use any other part of the building in order to cook, so using an external burner is not an option. So, my question is, how can I counteract th…

People, Been sellling aluminum for years- a 11,000ppm solution- simple- aluminum nitrate dissolved in a dilute nitric solution. Never a problem. Now, Im finding the solution is not stable for even 3 months. It looses about say, 2% strength/month, give/take. Just checked a stock bottle from december and its down 10% or so to about 10,000ppmAl. What is going on?? Where is the aluminum dissappearing?? Bottles always tightly capped. Oh- the way I test it is by classic titration- in ACS Reagents manual, if youre familiar with it. basically, its an EDTA back- titration, with dithizone indicator. very pH sensitive- gotta be 4-5.

Hi. Can PET be 'converted' into thermoplastic ethylene vinyl acetate EVA, polyamide, polyethylene, or polyolefin by some not too complex process ?

Hi, please can someone help me? I can´t explain why is 3:2 the best ratio for rocket. It is insane excess of sucrose, so HOw does it work? What equation describe this reaction? Thank you.

Hey! I wasn't really sure where to post this so please excuse me if it was wrong of me to post it here. Anyways, I was wondering if there exists some kind of computer programme where you can build molecules AND where they tell you if the molecule can actually exist. Thanks!

please read this, http://www.academia.edu/662030/Room-temperature... Then watch this, http://www.youtube.com/watch?v=UZMKIfFXw54 Let me know your thoughts on this matter, the goal is the get a higher yield of gold when the reaction is completed. Chloro auric is extremely expensive unless you are in singapore, that is why we need to receive the extremely higher yield. This video shows what we can do with silver but it's a cheap metal http://www.youtube.com/watch?v=fnyBldC4Ra4 Thanks

People, Have a piece of laminate wood flooring, was soaked with something- not sure. I suspect urine from dogs, or recent rain deluge seeping into the house (?). I strongly suspect pet urine from tenant. Any way for me to get sample of wood scrap, and test for urine residue? Creatinine? Amines? Tips /advice greatly appreciated.

I was bored so me and my friend made a hydrogen generator for fun and because we are both into chemistry. We mixed water with some table salt and added aluminum foil as the anode and cathode because my friend has seen it done before. We plugged it in to a 12v 850mah adapter and it ran for 5-8 seconds in the ventilated garage until I unplugged it, walked inside and dumped it down the drain. I remembered that table salt had chlorine attached to it so I didn't want chlorine gas to be produced. Did it produce chlorine gas? This was not on purpose but accidental. Did that 5-8 seconds do much damage? We both feel fine and had no shortness of breath or anything and we were a cou…