Science topics: Chemistry
Chemistry - Science topic
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds.
Questions related to Chemistry
The HC gas upstream T,P is known and downstream P is know. A cooling effect is likely to occur since moving from a high pressure to low pressure across the control valve. One of the things I am not sure how to estimate is the Joule-Thomson coefficient.
This nomenclature has confused me for years, and I have been told different answers. Does 1:1 25 mM AmBic/50% ACN refer to
A) a final concentration of 25 mM AmBic and 50% ACN,
B) equal amounts of 25 mM AmBic and 50% ACN mixed (final 12.5 mM AmBic and 25% ACN) or C) something else entirely?
If A, Then what do you do with recipes that call for 1:1 25 mM AmBic/ACN (implying 100% final concentration)?
Thanks for the clarification!
1.Looking for easy comprehensive and authentic books on analytical chemistry
I am already using
Harris Quantitative chemical analysis
Skoog and west
I just want to explore some book other than these!
2. Do tell me some good precise and easy to understand books on spectroscopy?
For example, which is more likely to oxidise to the equivalent phosphate, triethylphosphite or tris(2,2,2-trifluoroethyl)phosphite?
I'm interested in reading about popular research being conducted in the organic chemistry world. Any ideas where to start?
May we design intelligent reactions or intelligent reactant?
I would like to start a project for the construction of rockets as a project for high school students. Starting with the development of a solid fuel (KNO3 + sugar) which is the safest method for the production? What additives can I use? I have seen from very simple elaborations, to more elaborate methods with the same components. Heat the mixture and manipulate it how dangerous it is? How do I estimate efficiency?
I have performed a demethylation reaction using BBr3 and neutralized it with sodium bicarbonate solution and removed the water by lyophilization. Now, I want to separate my product from reaction mixture. My product is soluble in methanol and water. Could anybody help me to give idea for separation of the product?
I have to do few toxicity tests in which silver is involved. To do that i have to prepare a stock solution using silver nitrate (AgNO3) salt. The concentration of exposure in the tests is referred to silver itself, not to the compound. I need to know how much silver nitrate salt i need to have the concentration of 5 g/L of Ag. I would be really glad if someone could also explain/show the mathematical and logical reasoning behind the answer.
I am removing carbonates from clay and sand samples. So, I treat the sediments with H2O2. I need to wash the sediments to remove acid residues. I am thinking of heating the sediments with ultra-pure water over hot plate and subsequent evaporation. The process can be repeated for 3-4 times over hot plate. Will it work and act as an alternative method of centrifuge washing?
as i want to find out the impact of ceramide on my cells in DMEM-F12 medium. I dissolved C16-CER in Ethanol and added it to my medium. After having a look through the microscope, i see that it precipitates.
Does anyone have a solution for my problem?
And do you know if C2-CER is easier to use?
Dear one & all Kindly give the details for the similarities and difference between Article, Communication, Notes, Reports, Full paper, Featured Article, Perspectives, Review, & Tutorial ... How to select the suit one? What are the criteria for this? Most us select on the basis of length our findings; and present and previous work summery. This discussion is seems to be very simple.... but it is always better if we get an better idea of each one... May be it will help for research beginners..
Is anybody can help me to prpapre dual buffer system viz. Histidine-acetat, Histidine-phosphate, Histidine-citrate, arginine-acetat, Arginine-citrate
How can we select a dual buffer for particular pH reasons behind that.
In dual buffer how theory weak acid or weak base and its conjugate would work and chemistry behind if that
Whenever I pyrolyzed NaH2PO2, I am facing difficulties in cleaning the left over white residue (may be phosphates) in the tube.
So, I am looking for any effective cleaning protocols to get rid of this issue.
I am currently proposing a study about the formation of free PUFAs (EPA and DHA) in raw oysters treated with acidic sauces. Based on a study by Sajiki et al. (1994), free PUFA formation may be caused by the activation of lipolytic enzyme in the oysters treated with acetic acid. However, I am confused regarding this mechanism since the oysters are not alive. Can this explanation be used for dead oysters? Is there a better explanation for the formation of free PUFAs?
Here is Sajiki's study if you are interested:
Any answer or literature will be appreciated, thank you!
chemistry is one of an interesting science in the world. but in most developing country student is nit prefer to learn chemistry. i mention the most two cases: in developing country mostly no laboratory accumulation, and there is no reference materials and so on.
Technical papers or not
Is there one search engine that embraces all the detailed procedures and guidlines for lab scale processes and synthesis methods
While I am looking for academic positions in Canada, they are constantly asking for a research proposal in NSERC format. I never had an experience of making a proposal in that format.
Hence, I am requesting the research community here in to share their proposals. If you want to share with me only, please send it as a message. I will keep it confidential.
Any sample of proposal (awarded/non-awarded) in that format will be great help for me to fasten up and amend my proposal. I am very much grateful if someone can share their sample proposals.
Journal, Magazines and Letters publish scientific articles. What is technical difference between these articles and their recognition?
Writing Style, technical soundness, number of words etc.
A resazurin-based assay was produced with ampicillin against E.coli , negative control was just LB media and E.coli and the positive being ampicillin and E.coli, with resazurin for the readings. Plate readings were taken initially and then every 30 minutes for 2 hours. The only data I have is the plate readings and the initial concentration of ampicillin added. How would I work out the final concentration of ampicillin?
I want to mix Graphdiyne into NDP-V that is non-fullerene polymer and seldom used as electron transport layer. could you please predict its chemical properties or kindly send some research articles of someone already did it.
Thanks in Advance
At the brink of curricular reform in Czechia, we stand before the question how, if ever, to exit the traditional structure of lower-secondary chemistry curriculum.
We found several resources describing such initiatives, but so far nothing we could use to support our ideas during the talks with the policy-makers. Could you please refer us to some resources?
Thank you in advance.
I was once told that stable isotopes of lighter elements such as H, N C , etc are found in stars, planets, etc. Can anyone suggest any literature which talks about the formation of these isotopes?
I am using 1g/L stock solution of Copper and Zinc prepared from Copper Sulphate pentahydrate and Zinc Chloride, respectively. I am using the stock solution to prepare standard solutions of concentrations between 0.1 mg/L to 10 mg/L by dilution. I am preparing the standard solutions everyday by dilution from the stock solution to calibrate the Atomic Absorption Spectrophotometer.
My question is that is it OK if I store the standard solutions, which are of quite low concentration and use them for future use instead of preparing everyday from the stock solution? If yes, what is the maximum storage period for which I can use them?
Yesterday on December 5th, 2019 at 3:45 p. m. a full bottle of our homemade brandy on the small kitchen table on our kitchen spontaneously exploded. I am a retired university professor in chemistry and very knowledgeable in physics but I do not understand how could it happen?
I have been looking into MSDS of KOH of 0.1 M, and it says use proper ventilation area while working. But in my lab, we don't have fume hood to work with. And I am not able to find any safety sheet on 0.001 M KOH solution. I would also like to know about any possible health effects of this.
hello every one
I want to synthesis the CuInSexS2-x QDs and as I am elementary in chemistry, I want to know that how to determine the sub x in such structure in practice (mean in the synthesis of CuInSexS2-x QDs in Lab) ? and could you introduce me a source for more study about this fundamental issue in chemistry? thanks
Do there exist any compounds, fluorophores, dyes, quantum dots, phosphors etc that can emit or fluoresce non-linearly without needing ultra-high intensity illumination (such as pulsed femtosecond laser)? That is, with a UV led for example and with this non-linear emission being dominant?
Hi all, working on a task where HF acid gas may be present due to Li-ion battery combustion (faulty batteries, over-changing, transport/vibration) in a container. Curious how one would design a filter or neutralize this gas in order to lessen damage to humans and surroundings? I imagine this may be a chemical engineering question, which I have no experience with. Thank you!
I'm dissolving PCL in TFE for electrospinning purposes, and the paper I'm following has detailed how to do a 10% w solution by dissolving 0.4 g PCL in 4 mL TFE, but this doesn't seem right to me based on previous training I've received on how to calculate a w% solution which required me to dissolve 0.763 g PCL in 5 mL TFE. I'm feeling like the latter method is really a w/v%, but it always produced good results, so for future purposes which calculation should I go with?
I am conducting experimental simulations to study the PM 2.5 concentration.I have tried several chemistry options ranging from RADM2 MADE/SORGAM to MOZCART aerosol chemistry. The simulation was successful but I am getting very low values of PM 2.5 of the order of 0.1 to 0.9 ugm-3 which should be of the order 100 to 900 ugm-3. I am confused as to where I am making mistake. has anyone come across similar kind of issue with PM 2.5 concentration?. what should be my next step in resolving this issue?. I am using EDGAR HTAP and FINN data as an input data to include PM2.5 estimates. I am having doubts especially in the above emission input files. kindly check and see if there is any changes needed in the namelist flie of emission data especially the spc_map part of the namelist.
Anthro_emiss spc map emis_map = 'CO->CO','NO->NOx','SO2->SO2','NH3->NH3','BC(a)->BC','OC(a)->OC','PM_25(a)->PM2.5','PM_10(a)->PM10','BIGALK->BIGALK','BIGENE->BIGENE','C2H4->C2H4','C2H5OH->C2H5OH','C2H6->C2H6', 'CH2O->CH2O','CH3CHO->CH3CHO','CH3COCH3->CH3COCH3','CH3OH->CH3OH','MEK->MEK','TOLUENE->TOLUENE','C3H6->C3H6','C3H8->C3H8','NO2->0.0*NOx','ISOP->0.0*CO','C10H16->0.0*CO','SULF->0.0*SO2'
Fire_emiss spc map wrf2fire_map = 'co -> CO', 'no -> NO', 'so2 -> SO2', 'bigalk -> BIGALK', 'bigene -> BIGENE', 'c2h4 -> C2H4', 'c2h5oh -> C2H5OH', 'c2h6 -> C2H6', 'c3h8 -> C3H8','c3h6 -> C3H6','ch2o -> CH2O', 'ch3cho -> CH3CHO', 'ch3coch3 -> CH3COCH3','ch3oh -> CH3OH','mek -> MEK','toluene -> TOLUENE', 'nh3 -> NH3','no2 -> NO2','open -> BIGALD','c10h16 -> C10H16', 'gly -> CH3COCHO','acetol -> HYAC','isop -> ISOP','macr -> MACR' 'mvk -> MVK', 'ch3cooh -> CH3COOH','cres -> CRESOL','glyald -> GLYALD','mgly -> CH3COCHO','oc -> 0.24*PM25 + 0.3*PM10;aerosol', 'bc -> 0.01*PM25 + 0.08*PM10;aerosol','sulf -> -0.01*PM25 + 0.02*PM10;aerosol', 'pm25 -> 0.36*PM25;aerosol','pm10 -> -0.61*PM25 + 0.61*PM10;aerosol'
Hello RG fellows, I am trying to coat/deposit a thin layer via PECVD on Polypropylene substrate. The functionality of the coating will be water-vapor barrier. Which precursors are the best for this purpose? Thanks!
I'm creating an analytical tool for aromatic molecules that uses geometry optimization and connectivity data from Gaussian 6, but I'm having trouble with the connectivity output. When computing optimization with connectivity for Benzene using hf/3-21g, I receive the connectivity output:
whereas I'm expecting an output like this:
1 2 1.5 6 1.5 7 1.0
2 3 1.5 8 1.0
3 4 1.5 9 1.0
4 5 1.5 10 1.0
5 6 1.5 11 1.0
6 12 1.0
Does anyone have any recommendations about what basis set I should use or what I'm getting wrong?
Most of the literature reports that I came across are vague, especially the separation process.
So, I am looking for the tried and true protocols which can yield <10 nm MoS2 quantum dots.
Any relevant reading suggestions are also much appreciated. Thanks.
I’m trying to make a 4:1 ratio of two solutions. One solution is a 5mL soln. at 20% (w/v) and the other is a 100mL soln at 10% (w/v), respectively. Normally this is easy when both concentrations are the same, but how do I do the ratio with different concentrations? A mentor is recommending diluting the 20% solution to 10%, but this would defeat the purpose right? I’m sure there is a mathematical formula that would make things easier to understand. Thanks all.
I am trying to prepare CuN(CN)2 (=Cu[dca] = Copper(I) dicyanamide) by reducing an aqueous Cu(II) solution to Cu(I) with K2[S2O5] then adding stoichiometric amounts of Na[dca]. However upon addition of the reducing agent I form an orange/brown precipitate in a green solution, I believe this is as a result of the disproportionation of newly formed Cu(I) to Cu (orange/brown precipitate) and Cu(II).
The overall reaction for the reduction is as follows:
Cu2+ + 2HSO3- + 2H2O --> Cu+ + 2HSO4- + 4H+
And the disproportionation:
2Cu+(aq) --> Cu(s) + Cu2+
Are there any other reducing agents which may work better or any ways to stabilise the Cu(I) formed in solution to prevent the disproportionation and allow further reaction with Na[dca]?
I added V2O5 as precursor for vanadium 0.5g in 30ml of DI water. I added 0.5g of oxalic acid anhydrous in 10ml of DI water, which functions as a reducing agent. I added the reducing adent to the precursor solution, thereby my total volume now is 40ml containg V2O5 and oxalic acid. I stirred the solution for half an hour at 60C, but the solution only turned to green solution instead of blue solution according to the references. Can anyone explain it? I added oxalic acid anhydrous instead of oxalic acid dihydrate, could this be a reason?
Stable isotopes are defined as non-radioactive forms of atoms and they exist naturally in the nature. I would like scholars to suggest me some literature or any other aid where I can understand how isotopes are formed, in terms of energy levels and how can we create them artificially in the lab environment. Also, how are these stable isotopes more advantageous when compared to conventional element.
Can anyone please provide me pdf of this paper.
Interparticle Reactions: An Emerging Direction in Nanomaterials Chemistry
K. R. Krishnadas, Ananya Baksi†, Atanu Ghosh, Ganapati Natarajan, Anirban Som, and Thalappil Pradeep* 📷Department of Chemistry, DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE) Indian Institute of Technology Madras, Chennai 600 036, India Acc. Chem. Res., 2017, 50 (8), pp 1988–1996
I am working on several novel fuel cell types catalyzed by organic-anorganic composite catalysts and I am grateful that I was given a A4 sized piece of membrane made from quaternized Poly(styrene). I have been working on crosslinked PVA membranes but those really aren’t favorable since they don’t really have a high tensile strength and their consistency is rather highly flexible and rubber-ish.
Since I fear that the membrane will be used up in far future I will need an alternative for further work on my alkaline-anion fuel cells, now that I cannot use pva and since getting PVP for a PVA-PVP membrane is very hard here in Germany I need another idea for a making a stiff membrane.
Just dissolving regular PS, dissolving it and adding some Triethylamine as quaternizing agent probably won‘t work, will it? So are there possible alternatives to polymer membranes?
Hi dear researchers.
I have a mixture of nanoparticles and hemin and buffers, …
It was centrifuged and washed several times.
Is there any way to calculate the residual hemin concentration?
( There are not any biological samples)
i'm working on counter electrodes for DSSC. VO2 shows good thermochromic property. Are there other transitional metal oxides which show the same effect? What is the physics behind this significant property of VO2?
I read in a book Environmental Chemistry that" in anoxic region of water bodies , some bacteria use sulfate ion as an electron receptor where as other bacteria reduce iron(III) to iron (II). These two products react to give a black later of iron (II) sulfide sediment. This frequently occurs during winter, alternating with production of calcium carbonate by product from photosynthesis during the summer. "
Can anyone help me understand why this phenomena occurs during summer and winter??
I've a question regarding lipid oxidation - there are secondary products with truncated chains (like PoxnoPC and PazePC). The question is if they are stable, since I can't find any publication regarding the problem.
Hi all, referring to the table attached, it is seen that when ZnO NWs are doped with Bi at different concentrations, there is an increase in magnetization values initially. But we see by doping with Bi:ZnO at 3%, the Coercivity is increased linearly but on the other hand, Retentivity is decreased and then on doping with Bi: ZnO at 5% the Coercivity is decreased and Retentivity is again linearly increased. I need to know the physics behind this, please help me to explain in details. Thank you for your time and consideration.
#ZnO Nanowires #Zinc Oxide #Bismuth doping
I have micron-scale fillers (>10um) that I would like to utilize in a spin coating solution. I have been utilizing different chemical pathways to convert the initial filler product into a sol-gel solution. However, the particle size appears to be the same within my produced spin coating solution.
Would this particle size work within a spin coating procedure or does the initial filler size need to be in the nanoscale range? If it would work, do I need to tailor the spin speed to the particle size? If so, would getting to this tailored speed be trial and error, or is there a more sustainable way to get to my intended results. Thanks for your response in advance.
I’m pretty new to the world of data based Research, but as I explore deeper, I’m realising that I’m producing a lot of files that are becoming hard to track. I have a background in IT and VFX, where we have specifically designed tools to help with file management and organisation, so I’m a bit lost in terms of just creating a useful data structure.
I’m just wondering if anyone has any tips on storing, labelling, tagging and tracking the input, output and processed data in a convenient manner.
I’ve had a few friends within bio related fields suggest looking at NVIVO, though it looks like it’d be hell to set up for any small scale project.
Any help would be greatly appreciated,
I used hardened steel film applicator to coat epoxy based coating on metal substrates. Due to improper quick cleaning techniques, now there are some left over cured epoxy stains. How do I remove this ? I have tried to clean with acetone by dipping brush in acetone and rubbing the applicator. Right now I have soaked the applicator in vinegar . Am I moving in the right path ? Are there any better ideas ?
Note: I cannot abrade the surface because the gap in the film applicator will change. Only chemical methods are relevant.
Such as temperature, depth, chemistry, ph. What about for relative dating? Do gastropoda species useful for dating?
I am working on the synthesis of a 21 amino acid residues long peptide with the following sequence- NH2SSSDSSSDSSSDSDSSTDDSY-CONH2. The peptide has mutliple serines and a few aspartate residues. I am using the standard Fmoc coupling chemistry on microwave peptide synthesizer. After running a crude analytical HPLC run, I don't see the mass of the desired product and also nor do I see deletions of any residue. My question is can the synthesis of this peptide be difficult because of its sequence? How should I optimize my peptide synthesis? I was thinking of expressing it as a fusion protein in E.Coli in case my peptide synthesis route fails.
Thanks in advance
We know that boron nitride fullerene is more stable than carbon fullerene, but which one is the most stable in first principle calculation?
Does stability of BN-fullerenes is relative to number of B and N atoms?
I've seen the Modified Arrhenius equation in several forms. For instance, three kinds are attached.
Please consider the first attachment. There is an activation energy (Er). In some cases, authors do not use this form and they use the form just like two other form (see ar-2 and ar-3). They use "thetha" or "Tar". Now, I need to calculate Er from thetha/Tar. I think I have to multiply thetha or Tar by R. Am I right? R is universal gas constant and here its unit here is J/kgmol-K. I guess it should be 8314. Am I right?
How do I make up a 0.01M Na2HP04/NaH2P04 buffer solution, pH adjusted to 7? Both chemicals that I have on hand are anhydrous. The molecular weight of Na2HP04 is 141.96 g/mol and the molecular weight of NaH2P04 is 119.98 g/mol. Do I just dissolve 1.4196 g of Na2HP04 and 1.1998 g of NaH2P04 into 950 ml distilled water, then adjust the pH to 7 and make up to 1000 ml in a volumetric flask? Most of the methods I find use Na2HP04.2H2O and NaH2P04.2H2O. Thanks! (Please note that chemistry is not my field but I am helping out in the chemistry lab because we are short staffed currently)
I want to determine the pH of locally available
washing powder for a survey work. So, what is the appropriate ratio of sample and water for determining pH using electrodes?
I have a a question regarding surface modification of SiO2 chip. The presumption is that vapors of trimethylsilanol (CH3)3SiOH bond with the original hydroxyl terminated surface of the chip and cause wettability issues, not unlike the manufacturing process of hydrophobic sand (Magic Sand). Could someone please advise how would we go about removing these methyl terminating groups from surface and restore the original hydrophilic hydroxyl group termination?Oxygen plasma did not seem to have an effect on improved wettability. Surface is Si₃N₄, SiO₂, aluminium pads.
Thank you for ideas.
I have utilized FTIR (Fourier Transform Infrared Spectroscopy) to analyze and detect the material of my sample. The possible answers are obtained and I don't know which type of material they are! For example the possible materials for my sample are:
1. EMCOL K 8300
2. EMPIGEN BB
3. Methylamine (40%) on KBr plates
4. Sermul EA 54
5. Rewopol NOS 25
But I don't know what they are or what they mean!
Please find the results file (pdf) attached below.
Hi I am preparing enamel paint from alkyd of medium oil length. I found that the first coat of paint is getting tack free in 7-8 hours whereas the second coat is tack free in 5-6 hours. Can anyone explain this phenomenon of fast drying of second coat over the first one.
Does anyone uses Welch column 2.0 * 30mm, 30um for protein A analysis? If so, what is the column chemistry?
Most of the water-based rubber latexes show the behavior of non-Newtonian fluid while solvent-based rubber latexes behave as Newtonian fluid. It creates difficulties in latex glove dipping industries due to viscosity variation of rubber latex compounds such as neoprene rubber, nitrile butadiene rubber, etc. Is there any way to control and measure the viscosity of non-Newtonian rubber latexes.
PBS is commonly used for many purposed in the labs, most of the time it is freshly prepared but what in case it is made and kept for longer time. How long can it be stored and how to access its stability?
I need to conjugate a drug that have two secondary amine group (but doesnt have cooh group) with protein of my interest. As Edc/NHS coupling chemistry wont work well with secondary amines please suggest me what can be done in this case. Thanks in advance