Questions tagged [acid-base]
This tag should be applied to questions concerning acid and base reactions. An acid is capable of donating a hydron/ proton (Brønsted acid) or capable of forming a covalent bond with an electron pair (Lewis acid). A base on the other hand is a chemical species/ molecular entity having an available pair of electrons capable of forming a covalent bond with a hydron/ proton (Brønsted base) or with the vacant orbital of some other species (Lewis base).
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What is the degree of dissociation of Et3N [closed]
What should be the degree of unsaturation of Et3N. I'm trying to calculate and it comes out 0, but my text book tells me the answer is 3. I'm taking the number of C atoms to be 6 and H atoms to be 15 ...
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Lactic acid from calcium lactate & vinegar [closed]
I read that you can make lactic acid from calcium lactate and vinegar. Is this correct?
Suppose I want to add 10 g of lactic acid to water. How much calcium lactate and vinegar (5%) should I add?
It ...
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What do you think is happening to aluminium in salt water with rusted copper?
I put some aluminium foil and rusted copper(namely a Japanese 10 yen coin) in saturated NaCl solution.
After some minutes tiny amount of small bubbles were observed on the surface of the foil.
After ...
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Acid Base Introduction [closed]
What is the pH of .05M BaO? I have been trying to solve this problem for a while, but can’t seem to find a solution.
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Reaction of hydrogen peroxide with acetic acid and potassium permanganate
I conducted an experiment where I mixed hydrogen peroxide $\ce{H2O2}$, acetic acid $\ce{CH3COOH}$ and potassium permanganate $\ce{KMnO4}$ under vigorous stirring. The reaction hasn't stopped after 15 ...
user127378
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Can I use a mechanical pipette to transfer strong acid?
I am an undergraduate student majoring in physics. I am looking for the best method to accurately measure the volume of strong acids like hydrobromic $(w(\ce{HBr(aq)}) = 48\,\%)$ and hydroiodic $(w(\...
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Calculating pH of a solution of benzoic acid and NaOH [closed]
Calculate the final pH of the solution when $\pu{17.5 cm3}$ of $\pu{2 M}$ benzoic acid reacts with $\pu{25 cm3}$ of a $\pu{1 M}$ standard $\ce{NaOH}$
I found the number of moles of benzoic acid to be ...
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Is NH4HCO3 acidic or basic acid salt? [closed]
i am confused on NH4HCO3 being acidic or basic acid salt , even after searching there were not answers for this compound
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Does the acidity constant depend on the solvent?
Today I came across $pK_a$ values that depend on the solvent. For the hypothetical reaction $HA \rightarrow H^+ + A^-$, I had in mind that the acidity constant is defined simply as $K_a = \frac{\{H^+\}...
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How do clay particles form a colloidal mixture?
I have been learning about water coagulation in my chemistry textbook. Apparently, before being treated, water has clay particles, primarily silicates and aluminosilicates, which apparently have a ...
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Why can water act as a base under acidic conditions in organic chemistry mechanisms?
In Organic Chemistry mechanisms, I've commonly seen water getting protonated to complete a mechanism, and I'm getting a bit confused on how water can easily get protonated.
From the autoionization of ...
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Dissociation of Water?
My teacher told me that 1 in 553 million water molecules dissociate.
However, since water has a pH of 7, shouldn’t 1 in every 10,000,000 water molecules dissociate?
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Why and how do aqueous silica systems precipitate and can its occurrence be mitigated by quantifying its speciation correctly?
Background/Context:
For context, I have been doing a lot of work on experimental systems in geopolymer chemistry lately with a focus on "activator" solutions which are essentially mixtures ...
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What is the significance of charge balancing when analysing system speciation (carbonate system given as an example)?
Following on from my previous question and accepted answer, How do I quantify the carbonate system and its pH speciation?, I also calculated a charge balance ($CB$) on the system where $z$ is the ...
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Why does the pH of very strong NaOH solutions not make sense? [duplicate]
I'm wondering why the pH of extreme alkaline solutions, such as the case with $\pu{10 M}$ $\ce{NaOH}$ does not make practical sense and I'm wondering why this is the case? Refer to my calculations ...
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Can ions be acids or bases?
Consider a sulfate ion, its considered a weak base. Yet I thought bases and acids were compounds meaning they were always electrically neutral? Why is a sulfate ion then considered a base? And how ...
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A method to create NH3-NH4Cl buffer solution using titration method
My aim is to create a basic buffer solution.
I know that to create a basic buffer solution, we need a strong acid and weak base. In my case I have chosen $\ce{NH3}$ and $\ce{NH4Cl}$.
Using titration, ...
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Would an effervescent tablet react with itself if ground into a nanopowder?
Effervescent tablets usually are a mixture of a weak acid, base, and binder. When dry there is no reaction. But when placed in water the acid-base neutralization releases CO2 rapidly.
If you ground a (...
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Dissolving Pyrite with HCl: Will dissolving KNO3 in HCl give it a similar oxidizing effect to HNO3?
I'm trying to dissolve small pyrite (FeS2) grains. It's supposed to be done in nitric acid, but my lab doesn't have any. It does have a lot of 37% HCl and various salt oxidizers, such as KNO3, KMnO4, ...
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Why is the pH of this ammonia solution more acidic than another ammonia solution?
I made two similar ammonia solutions in different ways, and they resulted in different pH, but i'm not sure why.
Solution 1
Added 5.84 g NaCl to a 500 mL flask. Then added 10 mL 25% ammonia solution. ...
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Mechanism of the blue bottle experiment
I have researched multiple mechanisms for this experiment yet all of them suggest different versions or are too vague. None of them are consistent since the final overall equation seems to be missing ...
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Difference between change of enthalpy of neutralization between copper and manganese carbonate
I was doing a calorimetry experiment to calculate the change in enthalpy during neutralization reactions between metal carbonates and hydrochloric acid. I experimented with 5 metal carbonates: ...
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Why are the amino acids glutamic acid and aspartic acid considered the most acidic of the 20 if they are hydrogen acceptors and negatively charged? [duplicate]
I thought acids were proton donors or electron acceptor, not the other way around....
Also, arginine, histidine and lysine are usually categorized as basic, although they are hydrogen or proton donors ...
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Why did neutralization of weak acid calculation differ from empirical results?
I recently stumbled upon the problem of needing to neutralize a volume of 0.33M acetic acid with 0.1M NaOH. I was curious how many mL of 0.1M NaOH I would need to bring 1mL of 0.33M Acetic Acid ...
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Is hydrochloric acid or sulfuric acid more corrosive to titanium?
Which acid is more corrosive to titanium at 20 to 30 °C and similar concentrations: hydrochloric acid $\ce{HCl}$ or sulfuric acid $\ce{H2SO4}$?
I found some info on AZoMaterials — Titanium - Corrosion ...
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comparing basic strength of toluidine isomers [duplicate]
I would like to compare the basicity of ortho and para isomers of toluidine.After comparing the pKb values online the order of basic strength is:
p—toluidine> m—toluidine> aniline> o—...
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What drives double displacement reactions?
I have two questions:
I understand that in a displacement reaction the more reactive element displace the less reactive element. But why? In the reaction with Zinc and Copper Sulfate, we form Copper ...
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Question about aluminium and complex ion formation in water vs in acid
My textbook states, that aluminium reacts with water after dissolving the outer layer with HgCl2, and forms Al(OH)3, an insoluble compound:
2Al + 6H2O = 2 AI(OH)3 + 3H2
In non-oxidizing acids, it ...
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Does the nature of the H-A bond tell us about the $\Delta$G of an acid's dissociation?
When I first learned about acid strength trends in general chemistry, I remember it was explained in terms of the character of the H-A bond. The more polar the H-A bond, the easier it was to ...
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How do I quantify the carbonate system and its pH speciation?
I did Environmental Water Chemistry as part of my undergraduate course where we quantified pH-speciation for the full carbonate system and I got it right according to my tutor. My speciation profile ...
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Why acidity of hydrogen hallide increase down the group 17 [duplicate]
I just wandering when going down group 17 the electronegativity decreases, and acidity increase with an increase in electronegativity. Then theoritically it should have decrease its acidity of ...
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How specific is the exception of negative charge location (orbital vs atom) for determining stability of conjugate base?
Chapter 3 Acid-base reactions in Klein's Organic Chemistry As a Second Language explains an exception to the typical order of important factors for determining how stable a negative charge on a ...
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Why are nitriles less basic than amides?
Like nitriles have a localised lone pair which amides do not have, as their lone pair is delocalised and still amides are more basic. Why?
I could not find any satisfactory explanation so please ...
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How to establish trend of carboxylic acid acidity in the presence of certain substituents?
I encountered a question in my textbook which asked the following:
At first, i thought that i can approach it in the same way i sort the effect of EDG and EWG on the acidity of phenols, that is, ...
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When is NaHCO3 formed in the reaction between H2CO3 and NaOH
I my textbook, in the section on basic salts, NaHCO3 is stated as an example. However, as to how its obtained, the text mentions that it's just obtained by the reaction between H2CO3 and NaOH, hence ...
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What is the pKa value of the nitrogen atoms, specifically the amine groups?
How would you estimate the $\mathrm pK_\mathrm a$ values of the nitrogen atoms in 1,4-dimethyl-1,2,3,4-tetrahydroquinoxaline?
I struggle with it because I am unsure whether to classify them as ...
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Hydrofluoric acid
At work we have a large tank that is comprised mostly of hydrofluoric acid, I don't know the dilution factor as I'm not the one making the bath, but I have a question, when emptying the bath we tried ...
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Why do amphiprotic substances react to completion in acidic and basic conditions?
I was under the impression that amphiprotic substances were usually weak acids/bases. If this is the case, how could their reactions go to completion in more acidic/basic environments?
e.g. my ...
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intramolecular h-bonding in maleic acid
While studying organic chemistry, I came across two practice questions given by my professor:
Compare the acidic strength of:-
Maleic acid and Fumaric acid
o-nitrophenol and p-nitro phenol
And the ...
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Conductometric titration curve plotting
In the conductometric titation of HCl vs NaOH, the conductance initially decreases, reaches a minimum at equivalence point, and then the slope of the curve becomes positive:
Source: https://chart-...
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Quantity vs quality in determining acidic strength
Consider the following order of acidity based on pKa values:-
ethanoic acid > phthalimide >phenol >water >acetamide
Looking towards similar questions on stack exchange such as this
, the ...
user121185
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Why are amides weaker acids than water?
Based on a a recent question
I asked on ChemSE, the answer to my question was that amides are weaker acids than water with a typical pKa value of ~20. Although, this answers my question, it got me ...
user121185
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Why doesn't an acid-base reaction occur in basic amide hydrolysis instead of nucleophilic acyl substitution?
In the reaction of Grignard reagent with a primary and secondary amide, nucleophilic acyl substiution doesn't happen. The reason given is that R- is a strong base as well as strong nucleophile, an ...
user121185
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pH calculation of a mixure containing 2 strong acids and a buffer mixture
Calculate the pH of a mixtureof 10 mL 0,1 M HCl ; 5 mL 0,1 M HNO3 ; 10 mL 0,2 M HAc ; 15 mL 0,4 M NaAc.
My understanding was that I have to find the [H+] by:
finding the concentration of the products ...
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Notation for acid-base reactions of differing strengths - equilibrium?
I'm having trouble finding anything meaningful in textbooks or searches. My question is what is the correct notation for writing acid-base reactions when their strengths are varying? I know that ...
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Why is CaO a lewis base
We know that $\ce{CaO}$ is a base. But when I wanted to know which theory proves this fact, I got to know that Lewis theory explains this through a reaction with $\ce{SO_3}$. But the definition of ...
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What is Dornic acidity and how to measure it?
Context: I work with dairy product (cheese making) and in order to improve the quality of my process, I have documentation (in French) which refers to Dornic acidity over time.
This graph represents ...
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What is the number of acidic hydrogens and the n-factor of hypophosphorous acid?
My teacher said that the hydrogen which is directly linked with oxygen or more electronegative atom is an acidic hydrogen, and that the $n$-factor for an acid is the number of acidic hydrogens.
Then ...
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Do azaindoles primarily exist in anionic form at physiological pH and act as bases?
I am reading an article where they describe azaindoles (bicyclic pyridine/pyrrole rings) as being basic with $\mathrm{p}K_\mathrm{a} \approx 4.6.$
I suppose at physiological $\mathrm{pH}$ and after ...
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Are there any types of adhesive which are designed to be easily soluble in strong acid (HCl with pH 1-4)?
I am a mechanical engineer so forgive my ignorance in chemistry. I know there are water soluble adhesives like polyvinyl alcohol but I am wondering if there are glues which easily dissolve in low pH ...
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