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
Hello. I received a compound with molecular weight 453.292 and the only mass information for it is 1 micromol. This is very confusing because usually chemicals have a mass in grams or milligrams. I do not know how to calculate from this. I need to make up either 10mM or 1mM of the compound. Please can someone show me your calculation for either obtaining a final concentration of 10mM or 1mM (please show calculations for both, as i havent decided which one to make yet), how much DMSO I will need to use. Thank you
Im thinking about trying to synthesize some poly beta amino esters, however Im not sure if the chemistry is air sensitive or just water sensitive. The reaction is a polymerization reaction between amines and acrylates via Michael addition.
Also was wondering if you are supposed to remove the inhibitors from the monomers using inhibitor removal resin or keep them in, the materials and methods sections of these PBAE synthesis papers dont mention it, but it seems like something that would be necessary.
I've been noticing that after adding my blocking chemicals (TEA-Cl and CdCl2) to isolate sodium current, my pH increases beyond my ideal point (I'm trying to stick around 7.4 and it drifts to around 8.0 after adding both) and there is first cloudyness and then precipitate forming in the solution after addition of the CdCl2.
Prior to adding the blockers, I am bubbling my ACSF with carbogen for twenty minutes. I also do not add sodium bicarbonate or dextrose to my 10X stock. My concentrations for ACSF (working solution) are as follows:
Again, target pH is 7.4. Would really like some input on this, as well any any relevant chemistry as to what is happening. Thank you!
I am performing an experiment in which I am taking 35ml 100% ethanol in a small glass tank. I want to reduce this 100% ethanol concentration by a time-dependent chemical reaction. which reaction I can use for this?
Is there any accurate formula to find the diffusion coefficient of peptide and its ions (COO-) and (N+(CH3)3)?
My current work is producing a reasonable amount of dibenzyl ether contaminated with a small amount of dichloromethane, approximately 10% vol. I would rather reuse the reagent than throw it away, so can anyone recommend a simple method for extracting the dichloromethane.
I need to make the following HEPES buffer:
"Dissolve 1.6g NaCl, 0.074g KCl, 0.027g Na2HPO4.2H2O, 0.2g dextran (glucan or dextran) and 1g HEPES in 90ml of distilled water, ..."
The buffer is for plant leaf infiltration.
The instruction don't specify what MW dextran/glucan to use and dextran/glucan are really uncommon chemicals to have around. Is there anything comparable biochemically I can substitute for them? Maybe polyethylene glycol (PEG) or Ficoll?
Additionally, would using dextran sulfate be suitable to using dextran or would there be undesirable effects from the sulfates?
I am trying to imagine a problem where particles in water climb/coat onto an air bubble in bulk water. Is this even possible?
If yes, if we form equations, will that have the same surface tension as water-air (say 25 C) along with a force balance?
To complement this: Yes, using solid bubbles (say beads of glass) or simply a glass slide, we can make the water stick to it using surface tension
Your inputs are much appreciated! Thanks:)
It is clear that we use many types of hydrophilic additives containing hydroxyl groups in the PES dope solutions to provide a less hydrophobic membrane.
Is there any physical interaction between the sulfone group of PES polymer chains and hydroxyl groups of hydrophilic additives in the membrane matrix?
In Becke's B3LYP hybrid functional, Fock exchange is being mixed with Slater LSDA exchange (and then plus gradient correction), plus correlation expressions. But what LSDA exchange parametrization is used?
- It appears to me that Becke in his DFT Thermochemistry I paper (J. Chem. Phys. 96, 2155 (1992)) uses the VWN parametrization, being the then modern alternative to the older Perdew-Zunger version.
- Then in his Half-and-Half paper (J. Chem. Phys. 98, 1372 (1993)), he apparently switches to the then recent Perdew-Wang 1992 parametrization.
- In his 3-parameter hybrid (DFT Thermochem III) paper (J. Chem. Phys. 98, 5648 (1993)) he seems to only comment on correlation being taken from the PW 1992 parametrization and not mention which LSDA version he uses for the exchange part, presumabely still the standard Slater exchange (E_X ~ int n_(alpha)^(4/3) + n_(beta)^(4/3) dr.
So which LSDA parametrization is used nowadays in B3LYP? Did people stick to the VWN version from Becke's initial paper or did they switch to the more modern PW version as Becke probably did? Or do different implementations in program packages use different versions?
So I was running an IR on a sample that I had thought (or rather hoped) was phenol (hydroxy benzene), but what came out was either trash and noise, or I simply did not have phenol. My professor and I were quite stunned as it showed no signs of organic peaks at all, especially no -OH peak near 3100. My professor suggested to run my reaction again, but sadly I do not have the reagents on hand at the moment and it will be some time before I get them.
The reaction I ran was one taken from an old book on recycling benzene waste. When I conducted it, I took a mixture of nitrobenzene and benzene waste and I added a random amount of relatively pure Fe2O3 and 13% Hydrogen Peroxide to try and oxidize anything in the waste to phenol or hydroxynitrobenzene. After I treated it with NaOH to make a phenoxide salt and then I did some work up to isolate. What I was left with was a nice white crystalline salt (or so I thought). But the IR says it contains zero organics as far as our IR machine can tell, and our machine is used daily if not hourly, and is kept in great condition.
If someone could help me understand what I have or teach/lead me how to identify inorganics, that would be very appreciated.
Because the attached picture is possibly hard to see small details, I have listed the peaks as well.
-610.07 cm^-1 transmittance: 60%
-635.08 cm^-1 transmittance: 79%
-1091.13 cm^-1 transmittance: 64/65%
Rizal Awaludin Malik After rereading my notes, I have come to realize that I distinctly changed my procedure because I was having trouble with the Iron Oxides previously mentioned. My pseudo-procedure looks more like this:
Fe + 2HCl -> FeCl2 + H2
2FeCl2 + Cl2 -> 2FeCl3
FeCl3 + H2O2 (13% aq) -> Fe(OH)3 + Reactive Species
And my idea was to combine the benzene/nitrobenzene wastes I had with the final reaction in the scheme (combining the reactive species) to try and produce hydroxylated benzene and nitrobenzene.
Some notes from my notebook leave me further puzzled:
"Smell of nitrobenzene and benzene has totally disappeared, and lots of gas evolution. A red precipitate (likely iron oxides) has formed at the bottom of the beaker. There is no longer 2 layers (2 phases) and the yellow color of the solution is very faint, where it was quite deeply colored beforehand."
I'm not sure what exactly happened but I have done a little bit of searching and came across Hexaaqua iron (III) chloride, which may be what I have crystallized out.
To explain further, after the whole reaction was completed, I filtered off the red precipitate and tried to crystallize out whatever product I had formed. When I did so, I was left with a pure white free-flowing powder. The powder seems hygroscopic in nature.
I will likely try this again, with pure benzene to see if the same result occurs.
There were five pretests administered to both groups. Each pretest represents a different topic in chemistry (Matter and Its Interaction). In lesson 1, the experimental group has significantly higher group means than the controlled group. In lesson 2, two groups have statistically equal group means. In lesson 3 and 4, the control group has significantly higher group means than the experimental group. In lesson 5, the two groups have statistically equal group means. In the overall pre-summative test, the two groups have statistically equal group means.
Dear science community!
I need your help, please!
I`m totally disapointed and at a loss!
In 2020 (at the end of October) there were the IOP Conference Series: Materials Science and Engineering (ICoSiET 2020). Me and my colegues took part in these conference. As the result (like a result of any other conference) the thesis collection should have been published (at the 4th quarter of the 2020)). Unfortanately, these collection still haven`t publised (despite the fact that 2021 is already at its end).
So, I wonder, if there are anybody, who know something about this situation? Maby there are any of those who also waiting for their thesis?
We have wrote lots of messages to the organizators and the head of the university (in which this conference took place) but they stoped to respond us.
I think this situation shows disrespect for the conference participants. And I believe that such situations should be inlighted in our community!
Thank you, for your attention!
I have extracted polyclonal antibodies with PEG 6000 in PH (5.2, using HCL to adjust PH). Using dialysis membrane (12000 cutoff), the PEG was successfully separated from the polyclonal antibodies and I purified my product.
Currently, I am trying to establish product in industrial scale. But, I do not know what can be used instead of dialysis membrane in industry scale???? What is your suggestion? Could you please kindly help me regarding to the separation of PEG from polyclonal antibodies (180 KDa) in industry scale??????
What are the best books in chemistry that can be used for curriculum design "i.e. for Materials Chemistry"?
Please write the name of the best books that you read/know in the field of "chemistry"? General Chemistry, Organic, Physical Chemistry, Inorganic, Biochemistry, Polymer synthesis, Polymer Chemistry, Computational Chemistry, Solvents and Solvation theories, Analytical Chemistry, Electrochemistry, etc [...] and Chemistry Laboratory Design.
Thank you very much
- - -
* Additional comment:
You can, also, send to me links (or the books' front page photo) or E books (PDF or any) here or in private message. Thank you!
Good research is based on good relationship between the mentor or supervisor and the scholar. What are the qualities a supervisor or mentor must have to have a healthy and friendly environment in the laboratory?
I'm doing a survey as part of an Audacious program (https://www.startupdunedin.nz/audacious), which essentially is a StartUp initiative at Otago University. I'm curious to understand what level of programming do biologists these days need during their day to day research.
For all the biologists out there here are some questions to start the discussion on this topic:
1) Have you done any programming till date? If so which language did you use and for what purpose?
2) How have to overcome programming limitations? For example, did you get the work done through bioinformaticians, or sought help from your programming friend, etc?
3) Have you used online biological databases for your research? If so, which one?
4) How much of artificial intelligence have you used in your research? Do you see AI potential in your current work?
If you have anything else to add, please feel free.
I extracted the essential oil and I found that my major compound represent 95 % of the mixture and only less than 5 % as minor constituents ( 20 constituents).
I'm I allowed to take my major constituent as starting material to perform chemical reactions?
Do the minor constituents representing only 5 % will not disturb the obtention of the desired compound?
I would like to insert some functional groups to increase bioactivity.
Any help in this regard will be appreciated.
What kind of functional groups do we need to insert by the synthesis in organic chemistry to have anti-cancer activity in perspective?
Our publication house “M/s Har Krishan Bhalla & Sons” has been actively engaged for the promotion and utilization of essential oil bearing plants, and sharing the international research experiences in the field in form of a international peer reviewed Journal subscribed in Worldwide, Journal of Essential Oil Bearing Plants (JEOBP, <www.jeobp.com>) since 1998 aiming to benefit to all who have interest in essential oil-bearing plants.
Now, it has been planned to bring about a new Journal Entitled “Analytical Chemistry Letters” under above mention publication house.
Analytical Chemistry Letters is a peer reviewed international journal which provides rapid communication in all areas of Analytical Chemistry. Six issues per year are proposed and the first issue is planned to publish in January 2011. The Journal will also available online.
The journal publishes original research articles, short communications as well as review articles in all relevant areas of analytical chemistry which includes modern analytical and bioanalytical, Analytical Chemistry with multidisciplinary approach, Mass Spectrometry, Separations, Spectroscopy, Biological and Clinical sciences, Genomics and Proteomics, Medicinal Chemistry, Pharmaceutical Science, Pharmacology, Pharmacy, Natural Product Chemistry, Organic Chemistry, Food Science, Forensic Science, Environmental chemistry / analysis, Electrochemistry and Instrumentation.
We invite you please be a part of first issue and first volume of said Journal and send us 1-2 good articles for publication. Please send your article at the address given below, you can send your article by E-mail. For this the publication house shall be highly thankful to you.
Dr M K Verma
Analytical Chemistry Letters
Indian Institute of Integrative Medicine, Canal Road, Jammu-180001 (J & K) INDIA
Thank you very much. I look forward to hearing from you.
Arvinder Singh Bhalla
For “Har Krishan Bhalla and Sons
7/1/2C, Prem Nagar
Dehradun – 248007, India
I need to know that after dissolved EDTA in suitable solvent e.g. water, isopropanol etc.. what are the ionic species will form and how to confirm those ionic species presence using which characterizations? any references regarding EDTA dissolving reaction chemistry will be helpful. Thank you.
I have read few articles (mostly based on simulations) that show metal nanoparticles bond with graphene or graphene oxide. However, I am thinking about how can metal (i.e. 0 oxidative state which is already in the lowest energy form chemical bonds with graphene (with no functional groups) or graphene oxide (has functional groups). I personally believe that metal nanoparticles are mostly adsorbed (Vanderwall forces) and no chemical bonding can occur. Please let me know your thoughts.
I need the free amine of Cystamine for my next reaction step but Cystamine is only available as a HCl salt.
i cant find any procedures/instructions on how to release the free base.
I tried dissolving it in 2M and 10M NaOH solution and extract it with chloroform and then evaporate the Chloroform on the rotavap – did not work
I also added NaCl to the aqu phase to saturate it – also didnt work.
anyone who worked with Cystamine or Cysteamine before and has a clue on how to Free the base?
Dear to whom it may concern,
I wonder whether benzopyrylium ion is permanently or temporarily positively charged because I would like to convert its positive charge to its neutral form.
Would you mind if you may give me some suggestions in this case?
I see that silver mostly has a coordination number of two, and have seen to complex with two mono-dentates. Can Ag+ form complexes with di or tri or any polydentates ligands?
What kind of complex can Ag from with O- ? (when conditions are such that Ag2O does not form)
Kindly let us know the difference between white PAF and grey PAF. Will it cause any difference in the application?
Does these two types of PAF are used for separate applications?
Apart from chemistry, what is the difference in Super grade, grade I and grade II based on its applications
Which PAF is used for which specific application.
Thanks and regards
I am looking for a software that can predict the chemical reactions that will occur when I mix certain substances. For Example: Na+Cl --> NaCl.
I was preparing a phosphate buffer and adjusting its pH to 7.2 from 9.0 by adding monobasic phosphate. In the beginning, it started to decrease fast but then, it went slowly (it was about pH=7.6). Even though I added too much monobasic solution, its pH was not increased easily. Then, it went to pH=7.3 easily but it stopped at pH=7.3 again. I wonder why it happened. I know it is related to its titration and the titration graph is fine to understand but I need a comprehensive explanation for it.
We have small molecules, measured the critical micellar concentration. we getting keep negative value. it is a bit surprising. if anyone can explain the reason with support of literature will be helpful for us to come over the issue.
I've attached a picture of manually drawn organic compound using "Pubchem Sketcher". I was planning to synthesis this molecule using synthetic chemistry protocols.
Considering me as a fresher to synthetic organic chemistry, I'd like to learn more about the following questions.
1. What are all the different synthetic routes/steps that could be used to synthesis this compound?
2. How do I find the chemicals list, the steps involved, and the reaction environment required for this compound synthesis?
3. What are all the computational tools to predict the organic synthesis pathways?
If organic synthesis protocols for this substructure is available, please share them for references.
Hari Prasath Nagaiah,
- Product is achieved using 1:1.
- Oil route is used instead of methyl ester or FA.
- Reaction is conducted under ambient pressure throughout.
- Our color test is consistently below 300 alpha but we have received enquires on whether we can make Alpha 120 requirement?
- Kindly please advise what can be done to achieve this? Thanks.
Interested in knowing molecules with two or more sulfonic/phosphonic acid groups without a common endpoint (excluding phytic acid) and are available from natural resources or utmost commercially available.
Any relevant reading suggestions are also much appreciated. Thanks.
Please help me on how to synthesize low molecular weight N-methylol melamin resin that can penetrate the wood cell wall.
and what should be done to reduce formaldehyde emissions?
Thank you for your time.
Research chemists continue in their slow uptake of preprints. I've lately suggested one key reason for this unique behaviour of scholars in the basic sciences in two OA studies, one published by Publications:
and another by Insights:
What is your opinion on the origin of this delay? Has your team recently embraced preprint publishing? What are your favorite preprint repositories?
Thank you in advance for your insight.
I have a serious problem with coating the Pd/C catalyst uniformly on the glassy carbon.
I prepared the Pd/C ink by adding 20 mg of Pd/C into 9 mL of DI water. Then I sonicated it for 10 mins. I added 1 mL of IPA into the mixture and sonicated for another 10mins. I pipetted 5 uL of the ink on the center of glassy carbon (Diameter=3mm) and dried it in the air. To avoid any dusk from the air, I used a biker to cover the glass carbon. But I can't get a uniform layer of Pd/C catalyst on glassy carbon. Here is the picture of the Pd/C film. Can anyone help me with this problem?
I have to use a variety of chemicals to identify and separate out the different red pigments within certain species of crabs' eyes, one of which it is suggested to used acidified methanol for ommochrome pigments. However we do not have any premade in the labs and they have told me to make some myself and i have no clue what the best method (or acid) to use for this is. There are some papers that say to use hydrochloric acid and some that say to use sulfuric acid.
Please help me on how to synthesize low molecular weight phenol formaldehyde resin that can penetrate the wood cell wall.
Thank you for your time.
In the (electro-) conducting materials, as I know, there is an energy gap between the valence band (VB) and the conduction band (CB) that can be brought to or near-to the Fermi level by doping (p-type or n-type dopant).
But ( My question is ), If I want to design a (semi- or super-) conductor's materials (inorganic or polymeric) , Which properties would I look for? and, also, Which characterizations would I consider for the properties' investigations? What are the requirements for the materials' property (with regard to its band structure) to achieve the considered structure-property relationships (or requirements ) for the preparation of the conducting materials?
If there is a slight shift position of the functional group or peak intensity after the introduction of a Li+ source salt, what is the possible and reasonable chemistry? Please share if there are any reliable references regarding functional polymers and Li+ solvation chemistry. Thank you!
Hi everyone! I have a question for my farm compost.
So i just do my research and try to look for a compost with :
around 3.5% of Total N Content,
around 5% for my P2O5 content, and
around 1.5% for my K2O content.
And i just wonder, if i just combine :
Cocoa shell meal with 2.5% N, 1% P2O5, and 2.5% of K2O,
Worm casting that has 1.5% N, 2.5% P2O5, and 1.3% K2O,
Would it turns my compost into 4% N, 3.5% P2O5, and 5% K2O just like that?
i'm so confused as i'm not really good in both chemistry :D (as a geophysics engineer, chemistry is such a hard subject for me).
I have tried dissolving sodium oxalate in water and I am currently trying oxalic acid in NaOH however this does not seem to be working either. it wont dissolve and I cant find the answer on the internet anywhere. Someone please help
I need to choose a topic on design and analysis of experiment as a project. The project consists of planning, designing, conducting and analyzing an experiment, using appropriate principles and software package of design and analysis of experiments. Could you please recommend me an article or any reliable resources for the project? It must encompass 2 nuisance factors and topics such as Randomized blocks, factorial designs, 2k design and NOT RSM or CCD.
After the execution of the test of PDP ( Potentiodynamic Polarization) and the plot of Tafel curves, we need to extract to parameters from the plots in order to determine the corrosion inhibition efficiency.
We need Icorr ( current density) to determine the IE ( Inhibition Efficacy)
But, concerning βc and βa, where we can use them? Can we calculate something from them? Does the change of them from concentration to concentration of inhibitor say something?
PS. I'm doing only corrosion inhibition of Mild Steel in HCl, I'm using simple equivalent circuit containing Rs ( Solution resistance), Rct( charge transfer resistance), and CPE ( phase constant element).
Any contribution to this question will be appreciated.
When we used CTAB as a capping agent in reducing 4-nitrophenol by Ag NPs, Why CTAB is not good as much as SDS with the same reaction? What is the main reason with it?
In what case would a reaction rate always show direct relation with activation energy or would it always be an inverse relation? Is it a indirect relation, inverse relation or both case can hold? (Please provide supporting resource, thank you).
I would like to know which of these reactors is expected to record the highest conversion for CSTR and batch reactor when both reactors are assumed to have a similar volume, geometry, operating condition, and stirring rate (if possible do provide supporting resource/reference).
Thank you as you share your experience.
I am doing my thesis, this is about the design of a theoretical plant to obtain furfural. I need this book to know first hand: what are the by-products during the chemical reaction and how to calculate them? all this for a balance of matter. Excuse my english, thanks
One of the most major problems of writing an undergraduate article is the lack of access to a laboratory and a professor to check the accuracy of article information in the laboratory.
For example, at my university, only postgraduate, PhD and postdoctoral students are allowed to work in the laboratory. What should an undergraduate student do if he or she wants to write an article and extract the information needed for his or her paper from the lab?
Undergraduate students do not have access to professors and laboratories to verify their ideas, what should they do to write an article?
Can he write another type of article that is published in a valid journal but does not require laboratory information? Or can he collaborate with a foreign professor to write an article?
What is the solution to the problem?
Dear RG Academics who Travel,
This is an important topic because many academics relish going to desirable places for conferences. My husband and I used to travel to scientific conferences but so much red tape is involved he and I are glad to attend mostly on video conferencing technologies (yes, like Zoom and others whose names I don't know. No intent to favor one or the other technology company)
It is good to remember that social bragging rights do not equal additions to knowledge (i.e., what exotic place one has traveled lately.). Yet, local economies are helped by all kinds of conferences and the money that they bring.
There are costs and benefits either way, so please share your ideas about continuing in-person conferences when there is little we cannot do via remote presentation, informal conferring and virtual "hallway" chatter.
Look look forward to your ideas.
Interested in using commercially available heterocyclic/non-heterocyclic aromatic S-sources for making metallic sulfides under pyrolytic conditions.
Any relevant reading suggestions are also much appreciated. Thanks.
I have been preparing MoS2 through a hydrothermal process by combining thiourea and ammonium molybdate with 2.28 g and 1.2 grams, respectively, in a 35ml DI water and place it in 70 ml teflon autoclaves, at the end I would get 1g of MoS2 powder. Now, the issue is that I am forced to switch for thioacetamide as sulfur source, so I started with the same proportions as the thiourea (2.28g) but it appears that it is too much I get a very thick slurry in the autoclave instead of just light slurry that I can wash. So,any recommendations of proportions and weights that I can use to get similar results as the thiourea one?
Even though Artemis gives an error bar on the EXAFS fitting but it assumes the value to be zero at certain R values.
In the case of data with some experimental noise, the error bar needs to be corrected, weighted by the square root of the reduced chi-squared value, taking into account the experimental noise for each R-space spectrum from 15 to 25 Å, as described in
How do calculate the uncertainties in the coordination number when EXAFS is fitted using Artemis?
Thanks in advance
Hello, I'm an early career PhD student. When people ask me questions e.g. In conference or lab meeting, even when I know the answer my mind tends to go blank and I say I don't know just to get out of the situation. I used to be good at answering questions and taking time to think and answer , especially during my bachelors degree. As time was gone by I feel I have gotten worse mainly because I am afraid the answer will be ridiculous and made fun of as I have reached a very advanced level where everyone knows what they are talking about. After all these years sometimes I get tired of science in general and have no motivation to read up on my project , so sometimes I genuinely don't know the answers which makes things worse . I used to have a lot of passion which is what put me on this path, but at the moment I'm tired of science which is making it hard to answer peoples questions and i think people are starting to notice. My answers are generally non specific and waffley, and I was wondering if anyone has tips to overcome these problems. I am interested in my project and deep down I love science and wish I could do better and go back to how I used to be and express my answers logically and what is expected at this level. This is especially important for my thesis defense, I need help and tips please on how others process these questions and defend their work. This problem has also started to overflow into my writing where I can't think properly or focus with the overwhelming amount of information.