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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How to remove sulfuric acid from sample
I have problem with my experiment. My experiment is acid hydrolysis of ethyl benzoate. The acid that I used is sulfuric acid. My problem is when I get the precipitate (impure benzoic acid) I have to ...
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about acid-base equlibrium
I have one good question guys for chemistry community
Let me explain the question and i want satisfactory and simple tangible answer
Q: In Our chemistry lesson i.e "Acid-Base equilibria" we ...
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Why does my rainwater turn yellow if I increase the pH to 7?
My rainwater is colourless when collected, but if I add a small amount of sodium hydroxide to increase the pH to about 7, after a few days it goes yellow.
The colour change happens more quickly if I ...
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Why did hydrochloric acid cause copper to gain weight after soaking in it overnight?
I recently did an experiment involving 2M hydrochloric acid and two different metals, iron and copper. This experiment was to investigate how the metals reacted to the acid by letting them sit in the ...
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Why does the acidity order (CH₄ < NH₃ < H₂O < HF) follow the bond strength order (C-H < N-H < O-H < F-H) when stronger bonds should resist breaking? [duplicate]
I'm trying to understand the relationship between bond strength and acidity in the series CH₄, NH₃, H₂O, and HF. The bond strength order is C-H < N-H < O-H < F-H, meaning the F-H bond is the ...
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Mixing hydrochloric acid and sulphuric acid, both concentrated
In the chemistry lab, I stupidly decided to mix hydrochloric acid and sulphuric acid, both concentrated, in a random ratio, which was about $\pu{50 ml}$.
When I poured them in one test tube, the ...
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Can lead hydroxide react with potassium nitrate?
There's a chemical reaction where $\ce{Pb(NO3)2}$ reacts with $\ce{KOH}$ to form $\ce{KNO3}$ and $\ce{Pb(OH)2}$ (chalky white ppt).
But I have a doubt if the opposite reaction is possible too, i.e. $\...
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How to separate acid and base streams in water electrolysis
I am very new to chemistry and am trying to figure out how to separate the acid-base streams in standard water electrolysis. Namely, I want to end up with two streams, one of OH-1 ions and one of H+ ...
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Magnesium Bicarbonate Synthesis, How to be Certain of the Moles of CO2 added to Water?
Background Research
Through googling all I find is using chilled sparkling water or carbonating water and then adding a teaspoon of magnesium hydroxide to it.
The problem with these methods is that ...
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Redox mass balancing trouble
I'm a university student. I've been given the following redox to study and balance using ionic-electronic method:
$$CuS_{(aq)} + HNO_{3(aq)} \longrightarrow Cu(NO_3)_{2(aq)} + H_2O_{(l)} + SO_{2(g)} + ...
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Determine which ion, H3O+ or OH-, is in excess at the end of the reaction [closed]
How would you know when an acid or base is paired with $\ce{H2O}$ that it will form an $\ce{OH-}$ ion or a $\ce{H3O+}$ ion? I just started the acid and base equilibrium unit, and I'm just confused on ...
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Why is formic acid a stronger acid than acetic acid?
I am told that because the methyl group is electron donating in the conjugate base of acetic acid, this destabilizes the conjugate base by exacerbating the existing negative formal charge on the ...
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Acidity of toluene compared to propyne
Why is propyne more acidic than toluene? The carbanion formed in case of toluene is easily stabilised by resonance and -I effect of toluene. In case of propyne there is an electron donating ...
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Study of model reaction HCl + NH3 in water
I'm a student, and I've been given the neutralization reaction between $HCl$ and $NH_3$ to study. It Is asked to calculate how much acid is necessary to add to a $NH_3$ solution to make all the ...
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Acid/alkali + salt reaction?
Why some acid/alkali can react with some salt, forming another acid/alkali? For example:
$\ce{2NaCl +H2SO4->Na2SO4 + 2HCl}$
$\ce{Ca(OH)2 +Na2CO3->CaCO3 +2NaOH}$
but not the reverse.
What ...
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What pH will a pH 13 sodium hydroxide solution drop to exposed to air, and how fast?
Let’s say I dropped a bottle of lye heavy, liquid soap with a pH of 13.
If this soap lies around exposed to air, what pH will it drop to once the sodium hydroxide has turned into sodium carbonate? And ...
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How to mitigate salicylic acid saponification?
I started to make soap a few months ago and came up with a few formulas, one of it contains salicylic acid as a exfoliant/anti-acne agent, I've just realized that since salicylic acid is, well, an ...
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Why can't we write the buffer equilibrium equation as [duplicate]
Suppose we have a buffer of ethanoic acid and ethanoate ions in a buffer system. All I have seen people use to represent this buffer system is
$$\ce{CH3COOH + H2O <=> CH3COO^- + H3O^+}$$
But ...
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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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Pipetting strong acid with plastic material
Can I pipette concentrated sulfuric acid using a plastic pipette tip? Will either the plastic or the acid be affected?
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How will acetic acid behave in specific solution?
For my experiment I have a 1:1 solution of 1.5 (w/v) chitosan and sodium-alginate (SA) in deionized water separately. Beforehand, I had to dissolve the chitosan-powder in 1% acetic acid solution.
I ...
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The pKa of 3,4-dihydroxycyclobutane-1,2-dione (not squaric acid)
Would like to know if 3,4-dihydroxycyclobutane-1,2-dione reacts with NaHCO3 to give effervescence?
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Help troubleshooting inconsistent pH measurements
We're a small homestead cheese manufacturing company. Recently we've done R&D for cheese that's salted by means of a brine.
Problem: we have had inconsistent pH readings and we are left confused ...
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What ratio of bicarb to vinegar do I need in order for the result to be pH neutral?
This question stems from one I just asked over at Seasoned Advice, where my recipe tasted decidedly off because the pH was wrong.
The recipe called for $\pu{16 g}$ bicarb of soda (sodium bicarbonate, $...
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Are acids effective in removing soap scum?
In my experience, most of the commercial products intended for removing soap scum from bathroom surfaces are ineffective. No matter how long you leave it on or how hard you scrub, the soap scum doesn'...
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Why is a borax solution basic?
When searching the wikipedia link for borax, it tells you that dissolving borax in water gives a basic solution.
On further inspection, one site lists the reaction equation (https://www.vedantu.com/...
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PREPARATION OF SALTS [closed]
A liquid turns white anhydrous copper sulfate blue and has a boiling point of 103°C.
Which could be the identity of the liquid?
A alcohol
B petrol
C salt solution
D pure water
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Why does polonium form acidic oxides?
All metals form basic oxides. Metallic oxides are basic in character.
Polonium is a metal, so it should form basic oxides but it forms acidic oxides. Why are its oxides acidic in character?
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Only the Hydrogen ions bonded to oxygen are replaceable in Phosphorous acid. Why?
The basicity of Phosphorous acid is 2 though it has 3 Hydrogen ions. I heard that it is because only the hydrogen ions bonded to Oxygen (Only 2 H ions) are replaceable. Why is it so?
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H+ concentration of the mixture of a strong and weak acid
I reviewed the complete solution (hand-written) to the problem at Calculation of the pH of a mixture of a strong acid and weak acid.
My question is why it is okay to apply the K1 value for the weak ...
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How can adding a strong base to a weak base be the same as a strong base in solution problem?
In professor's lecture on acid-base titration, professor says (at this point of the video, link should start about the time she says it)
"adding a strong base to a weak base should be treated as ...
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Why would the theoretical pH not match the measured pH when performing a titration of NH4OH with HCl?
I ran a weak base - strong acid titration experiment using an automatic titrator. I started with an aqueous ammonia stock solution (somewhere in the range of 0.1 - 2.5 wt.%) that was left open to ...
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Stability of carbenes
For predicting the order of formation of carbenes from the following compounds (CHI3, CHBr3, CHF3), we can take a look at the stability of the halide anion that is formed (I- vs. Br- vs. F-) and the ...
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Irreversible uncharged acid/base indicator
I am conducting a process in an electrochemical cell where at the cathode or anode surface the pH might be acidic or basic. To figure out if either one is correct I would like to find a reaction that ...
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What is the pH of acetone in water?
Reaction of Acetone with Water
Acetone in water can react in three ways:
The different reactions change the concentrations of $\ce{H+}$ and, consequently the pH, differently. My question is what is ...
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Vinegar salt reaction to produce acid; does it matter what type of vinegar I use
I am trying to get get hydrogen chloride gas by using the reaction sodium chloride + vinegar = HCl(g) + sodium acetate, does it matter what type of vinegar I use eg apple cider vinegar, malt vinegar; ...
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Alkaline + Sweat + heat = cat piss? [closed]
Back in the 70s my Army unit spent three days in the Arizona desert, temperatures reached over 110°, we only told to only bring one set of camouflage fatigue. After the maneuvers we were bussed to the ...
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pKa of acetic acid in pure NH3?
Acetic acid completely dissociates in liquid ammonia and I would like to know the $\mathrm{p}K_\mathrm{a}$ value for the acid in that solvent. Can anybody point me to a reference?
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Acidic strength comparison of squaric acid and rhodizonic acid
These two are dibasic acids with the following structures (squaric acid and rhodizonic acid in order).
Empirical evidence proves that squaric acid is more acidic than rhodizonic acid.
It is a ...
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How can I identify whether a substance is KOH or NaOH?
I've bought $\ce{NaOH}$ or $\ce{KOH}$ (I don't remember which one!) for my electrolyzer and I've tested it. Now I want to improve its performance and I was searching for a better electrolyte when I ...
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Reaction between sodium bicarbonate (baking soda), isopropyl alcohol, and acetic acid (vinegar)?
I observed this reaction by playing around with vinegar and baking soda and I do not completely understand it.
Everyone knows that baking soda (sodium bicarbonate) and vinegar (acetic acid) go crazy ...
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Why should the pH change when I add sodium hydroxide to water? [closed]
I am a student and I am trying to understand the concept of pH.
If I add pure $\ce{NaOH}$ in water, it leads to the formation of $\ce{OH-}$ ions in the water. But this shouldn't lead to any change in ...
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Calculating the heat of reaction between sulfuric acid and sodium hydroxide
For my lab report I have to calculate the theoretical heat of reaction $\Delta H_{\text{rxn}}$ between sulfuric acid $\ce{H2SO4}$ and sodium hydroxide $\ce{NaOH}$ using their heat of formations. The ...
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Non-binding buffer at pKa of roughly 6 that dissolves in ethanol?
I'm trying to find a proper buffer for my experiment, which I'd appreciate some suggestions on. I have a solution in which I want to measure the concentration of magnesium ions using a fluorescent ...
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Determination of the composition of the mixture based on acid-base titration
The solution can contain $\ce{HCl}$, $\ce{H3PO4}$ or $\ce{NaH2PO4}$
individually or in all possible combinations. An aliquot of
$25.00\,\text{mL}$ of this solution consumes $14.56\,\text{mL}$ of
$0....
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Why is phosphoric acid a weak acid?
What is the reason for the phosphoric acid $\ce{H3PO4}$ being a weak acid despite having a structure similar to that of sulfuric acid $\ce{H2SO4}?$
I found some sources claiming that the resonance of ...
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The effects of acetic acid on porous concrete brick and mortar joints
I mistakenly applied a patio cleaner containing acetic acid to my porous concrete facing brick thinking it was biocide. The concentrate solution has a pH of 3 and I diluted it to one part concentrate ...
CommunityBot
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How to identify an organic base?
According to the answer key, trimethylamine (iii) and ethanolamine (iv) are considered organic bases, whereas ammonium (i) and acrylamide (ii) are not:
From my understanding, an organic base has an ...
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Why is Piperidine more basic than Pyridine? [duplicate]
Piperidine, which has sp3 carbons attached to it, experiences an increase in electron density on the nitrogen atom, making it more basic. However, when we look at the resonating structures of pyridine,...
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Why is a basic (not acidic) electrolyte frequently suggested for electrolytic de-rusting of metal or iron objects?
For home or do-it-yourself electrolytic de-rusting of steel or iron objects, the use of a soda-based electrolyte, such as "washing soda" (sodium carbonate) is almost always mentioned.
I have ...
