Acids - Science topic
Acids are chemical compounds which yield hydrogen ions or protons when dissolved in water, whose hydrogen can be replaced by metals or basic radicals, or which react with bases to form salts and water (neutralization). An extension of the term includes substances dissolved in media other than water. (Grant & Hackh's Chemical Dictionary, 5th ed)
Questions related to Acids
I've been searching for a method to dissolve those catalysts for ICP-AES, but I couldn't find anything. Ir is expected to be as IrO2 and so far I only found that hot HCl could work. For CeO2 I found that HNO3-H2O2 (1:1) will work. I don't know If I should use a mixture of everything or just focus to dissolve Ir as it is the main material to analyse. Suggestions?
I have seen numerous excellent research papers where metallic nanoparticles are used as carriers for enzymes or acids in lignocellulosic biomass pretreatment. But is it possible where the nanoparticles alone will help in the breakdown of biomass into simpler sugars.
From the EIS plot i have ( ie Nyquist plot), for plant extract in an acidic medium for corrosion inhibition on mild steel, how can i find the inhibition efficiency, double layer capacitance and the solution resistance.
There is a USEPA standard on this I believe, but I am having trouble finding it. Our lab washes dishes and we place dried dishes in the HCl acid bath to remove contamination but focus especially on phosphorus removal. We need to have the volume of the bath increased a bit (it is about 6L).
I need some 2-substituted malonic acids. For example 2-(adamantan-1-yl)malonic acid. It is easy to prepare corresponding ethyl or methyl ester. But any attempts to hydrolyse it lead to decarboxylation. In my example the only product is 2-(adamantan-1-yl)acetic acid.
What I have alredy tried:
LiOH, NaOH, KOH in various concentrations in water and alcohol solutions
Freezing reaction mass down to -19C
Various concentrations of HCl in water.
Please let me know if there is any working method to hydrolyse such esters or another approach to synthesize 2-substituted malonic acids.
Is there any esay way to clean quartz uv cuvetts from hard sticked precipitites using availble chemicals in the lab such as acids or basis, not expensive commercial products ?
So far I have seen that organic acids are used to kill off spent yeast from the brewing industry before being fed to animals such as pigs. The amount of acid needed to achieve a satisfactory kill off seems to be quite cost prohibitive so I was wondering why I have never seen formaldehyde containing products being used for the control of yeast in animal feed in regions where formaldehyde is allowed? Thanks
I'm trying to obtain xylose crystals from the aqueous phase of an acid hydrolysis-derived process. After evaporating the water, we performed an ethanol extraction in cold. It was supposed to yield xylose crystals, but I had none. Would any of you recommend a different protocol?
I wish to measure the total protein concentration of some samples but my standards are always bended rather than giving a nice straight line.
I first tried to make the standards with BSA but also tried Ovalbumine. Here I though that maybe my Bicinchoninic acid has went out so I bought a BCA kit but I keep having the same bended standard curve (see image)...
Has anyone any idea of what is going on? What can I try to fix that?
Thank you for your help,
Currently, I'm searching the best method to quantify Jasmonic Acid in plant tissue. Previously I have tried to analyze by using GC-MS but I failed. I am planning to try HPLC and the available HPLC that I had found is UV-detector. Can anyone who had an experience on this analysis advise me, what is the best gradient elution to apply with a mobile phase of acetonitrile and triethylamine? Or any other suggestion? Thank you in advance.
Salt formation of weak acid causes ionization of drug due to which solubility increase but we have studied drug absorbed in unionized form then how salt formation will improve the absorption of a drug?
How can I maintain a pH lower than 3 in an aqueous solution when using metallic iron as a reductant, considering that the iron's reaction tends to increase the pH? Any recommendations for suitable buffer solutions or methods to achieve this?
Where does carbon go during decomposition and decomposition of organic matter contribute to the development of soil acidity?
In supercapacitor ,generally we use aqueous electrolyte and if we use 1.23 V above which water molecule splitting will happen.
I want to purify indomethacin in ethanol but the problem is the formation of ester impurity due to esterification of acid part of indomethacin with ethanol. Is there any way to prevent estrification?
I found difficulty in synthesizing of 2-hydroxy-5-nitroisophthalaldehyde from p-nitrophenol by using duff reaction(HMTA, Trifloroacetic acid at 110 oC) having yield around 4-6 %
please provide ortho- diformylation of p-nitrophenol. Is there any other condition to apply for it?
What is the most suitable solution for reducing pH of an solution which contains L- amino acid and peptide in a non-destructive way?
The protocol we use is the two-step desolvation method using acidic pH, but it seems that instead of a powder we seem to get fibrous cotton-like material instead. Has anyone else experienced it and how were you able to solve the problem? Thank you very much!
It seems that calcium dipicolinic acid (Ca-DPA) and dodecylamine are not soluble in water.
i have done several samples using sebacyol chloride, however the TGA results not as wished. Any tips for the amount of monomers.
When we add organic matter in the form of biochar or compost to acidic soils, the organic materials decompose and release alkalinity such as carbonates, organic anions, inorganic anions, organic surface functional groups, and other organic compounds to the soil to neutralise acidity and raise soil pH. However, all the organic compounds generated from organic materials are not soluble in water to raise soil pH.
Which of these organic compounds or others not mentioned here, which are derived from organic materials, are soluble only in acids such as 0.5 M HCl and which of them are soluble in water as well?
I appreciate your time to answer this discussion question.
I am using the SSX system for the selective extraction of transition metals. In the SSX system, one is an acidic extractant and another is a basic extractant. I need to maintain constant pH for extraction when I am going to test the performance of different ratios of these two extractants. I read some papers and found that they mentioned the study of different ratios of the extractants at particular pH but I didn't find any mentioned information about this that how can we maintain the pH. If anyone has any ideas please share.
In the acid hydrolysis step of nano cellulose extraction , recent literatures are citing oxalic acid treatment in comparison with sulphuric acid
Trimesic acid is reported to be soluble in water (26,3g/L, Sigma) but I see that most publications use a volume mixture 1:1 water:ethanol. Is it related to the kinetics of the dissolution? Do I need to increase the temperature in order to obtain the solubility reported?
Currently, I'm working with ICP-Ms but unfortunately in my country is really difficult to buy ultra-high pure nitric acid. Therefore, I thought of distilling the acid to eliminate the metals present. But I don't know if this would help me to reach the desired purity.
Any suggestion on the purification process would be highly appreciated. Thank you!
I conducted heavy metal analysis by ICP-OES of a dust sample in a few months of gap.
What I found was that the concentration of many elements was not the same as earlier results like it increased many folds but some metal's concentration were approximately matching.
I used an acid digestion technique to digest the dust samples and then made the final volume of 100 ml for each sample for analysis with distilled water.
What can be the reason for this?
Which microbial organism grows best in acidic habitat & microorganisms are most efficient organic matter decomposers under acidic soil conditions?
I want to study the extraction performance of acidic extractant in different pH
I need to passivation on the nickel film to create a polymer structure, but in acid this is not possible, the film goes away instantly. How can passivation be achieved other than acid?
Chantal Jeanne Beauchamp with colleagues (1990)
Is there any report about fungi grown on cucumopine?
I want to know if there is any general notation regarding the surface acidic properties of spinel phase catalyst. Does acidity increase or decrease after a bimetallic catalyst's phase change (spinel)?
Is it possible to remove N-Boc protection group simply by heating? The t-butyl protecting group of –COOH can be removed by heating at a high temperature (160 °C for 15 h) without acid/ water. But is it possible to achieve this in an amine system (preferably at temperatures < 120 °C )?
Please share your valuable opinions about this.
PBS buffer pH value is about 7.4 and Now a days the biologists use PBS buffer tablets which have a concentration of 0.1M and pH 7.4.Although PBS is made up of four constituents ( NaCl, KCl, Na2HPO4 and KH2PO4 ) can we make it the pH changes to 5,6,7,8,9 by adding acids and bases like NaOH and HCl/H3PO4 ?
When analyzing the structure of pectin polysaccharides, in addition to nuclear magnetic resonance, is it necessary to conduct methylation analysis? Pectin is an acidic polysaccharide, and methylation analysis is still difficult to operate. If we have done 1D and 2D NMR, can we not conduct methylation analysis? Because a few journal articles did not conduct methylation analysis either.
After transferring the acid detergent fiber (ADF) in 72% Sulphuric acid and asbestos the solution is filtered with Whatman No. 1 filter paper. But the filter paper was not dried in 100degree Celsius for 3days. Any suggestion regarding the drying of the filter paper is appreciated.
I am afraid of overshooting the pH of hydroxyapatite solution by combining, Ca(OH)2 suspension and phosphoric acid. Can you suggest an acid solution to adjust the pH=10?
Recently I learned that I could use 28%-30% ammonia solution in increasing the pH=10, what if I accidentally surpassed, what acid solution and concentration should I add?
I would like to make a collagen I coating.
Is it possible to adopte directly a buffer solution to dissolve collagen powder reaching a specific concentration?
Or do I necessarily have to use an acid, such as acetic or hydrochloric, first and then dilute it with buffer?
Thank you in advance.
I'm trying to synthesize malonyl dichloride from malonic acid using POCl3 as the chlorinating agent. I'm adding dropwise the POCl3 at 0 Celsius degrees to the solid malonic acid and stirring the mixture for 30 minutes according to an article I read recently, but no reaction seems to take place. I left it stirring overnight but the next day what I saw was just the solid malonic acid stirring in the liquid POCl3. Any advice on how to help the reaction take place?
I'm trying to thiolate Poly(Acrylic acid) (PAA) with L-cysteine using EDC (or EDAC), however prior to the addition of L-cys, when I add EDC to PAA large clumps form in solution.
1g of PAA was dissolved in 100ml of deionized water, and 2ml of EDC was dissolved 10ml of water. The pH of both solutions was adjusted to approximately pH 5. The EDC solution was added dropwise to the PAA dropwise over 30 minutes, with stirring. The polymer started to clump together upon the addition of the EDC and failed to dissolve fully. Any suggestions as to why this may be happening?
I am currently doing research on Biosurfactant production, esp Rhamnolipid. From a few article that i read, it is possible to estimate Rhamnolipid percentage using Orcinol-Sulfuric Acid method. I would like to know if it’s possible to use Orcinol monohydrate instead of Orcinol for this method.
It will be so much help to me if you could give me an answer.
After deactylation of chitin from snail shells, i have washed the filter residues so many times with hot DW, but it is still strongly alkaline. Can I use dilute HCl in washing and what Molarity is best?
I want to quantify the hydroxyaromatic acids such as 2,5-dihydroxyterephthalic acid, 2,5-dihydroxybenzoic acid and benzoquinone, and hydroquinone with HPLC.
The HPLC column I have in my institution is Poroshell 120 EC-C18.
what are the conditions of HPLC analysis to verify the listed material?
I have performed the nitration of 2-hydroxy-5-nitrobenzaldehyde in various conditions (for example, in the presence of sulphuric acid or acetic acid). However, in all cases, the precipitate that I received at the end of the reaction was an initial compound (2-hydroxy-5-nitrobenzaldehyde). Which methodology should I use?
Currently, I am trying to degraded polymer PET into TPA and nylon66 (PA66) into hexamethylene diamine product at the same pot reaction using microwave digestion. However, this two type of polymer could not simultaneously degrade. I have already tried in different route of acid and alkali. The product that I obtained was only the degraded nylon66 (adpidic acid and hexamethylene diamine) while the PET could not digest at the same pot reaction. Is there anyone has experience on how to depolymerize of PET and Nylon66 at the same time? or do you have any research paper work that could help me to solve this out ? Thank you so much for your kindly suggestion and comment?
Hello, I'm trying to synthesize a ligand named 2,5-dihydroxiterephthalic acid. How can I measure the conversion ratio of reactants?
I attached a patent that did this and measured the conversion. I'm wondering to do the same measurements for my reactants and products.
I will be thankful if somebody helps me with this. I really need to solve this problem for my master's thesis.
I'm trying to produce GelMA, but I'm losing product's weight on dialysis. Firstly I thought that the membrane had problem, but I'm still losing with a new membrane. I'm thinking about the hidrolysis, but I can't find the pH range for alkaline and acid hidrolysis.
In acid persulfate digestion method for measuring phosphorus and nitrogen concentration, digestion process needs to be done by autoclave. Is there other alternate of autoclave to digest the sample?
Please what is the best method to use to dissolve Eucalyptus leaves to extract the gold from the leaves! we used NACN (SODIUM CYANIDE) it works good but it is very dangerous and not safe to use this acids, i think Aqua regia will work good, or what you think ?
please let me know!
check the attached file 📂 for more details about the gold particles in Eucalyptus leaves :)
In high temperature sulfuric acid peroxide mixture (SPM) cleaning process, H2SO4 reacts with H2O2 and forms H2SO5 i.e. called caro's acid. Caro's acid is very reactive at high temperature with volatile organic contaminations. But question is, how and why this acid react with contamination ?
For measuring the titratable acidity, I see titration of sample with 0.1 N NaOH to reach specific pH and reported by lactic acid. But the specifi pH I see is different in literiture, which one I should choose? does pH depends on the type of sample we have? For example I see pH is 6.6 or 8.5 or 7.4. I am confused ed please let me know your guidance. Thank you.
Also, is ''titratable acidity'' the same as ''total titratable acidity''? thanks
Greetings I'm a bit, if not saying a lot, rusty in this pH exercises.
Imagine you have 1L of a solution of salts dissolved in water which becomes stable(in equilibrium) at pH 7.2.
Can we predict how pH will change if we further add 500mg(let's say) of MgCl2 or MgSO4 to the solution?can we know which of these would vary more the pH of the system?
Does it depend mainly on basicity of Cl- and SO42- or do we need to have in account the initial pH and the salts already dissolved. And would the effect vary if we add the hydrated forms of the salts instead of the anhydrous forms?
My guess is, as Mg2+ is a common ion in both salts, the major effect would come from the counterions in this case Cl- and SO42- with which we would have to enter with Kb of this two ions. Is is as "simple" as that or am I forgetting something?
The pressure increases suddenly with every injection from 120 to 300 bar and decreases to normal in 20 sec or by switching the valve to mainpass Why?
Agilent 1260 series HPLC
MP: MeOH:ACM:Water (48:48:4) isocratic
Column: Phenomenex Luna C18, 3 microns, 4.6 mm, 150 mm with a guard column
Column temp: 50C
Flow rate: 1 ml/min
Injection amount: 50 microliters with an autosampler.
Samples in ACN with a strong acid (TFAA)
A very good day to all of you.
I have a question regarding solvothermal preparation of TiO2. Is hydrolysis rate is important in the solvothermal process? Is it bad or good? How does the acidic condition during the solvothermal preparation affect the hydrolysis rate?
Thank you in advance!
I usually use nitric acid as a washing filter glass.
Sometimes mix with ethanol.
I found some acid like hydrochloric acid and phosphoric acid.
So here is the question.
Does acid like hydrochloric acid and phosphoric acid can be used to wash filter glass?
I would like to conserve root samples for FCR analysis until I receive the chemical product bathophénanthroline disulfonic Acid 98% needed for the analysis.
Could you please inform me about the best way to preserve root samples for this kind of analysis?
Does freezing at -30°C enough? or-80°C?
Thank you for your help.
Dear Seniors, and scientists,
Can someone please guide me that why International Unit (IU) of activity for vitamin A are replaced by Retinol Equivalent Activity (REA)? Why it's Retinol and not Retinal or even retinoic acid?
Thanking you in advance.
Hi, every one, please i need to quantify the retinoic acid in brain and plasma by HPLC and i need protocols for that, thank you for helping