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 is on the other hand a chemical species/ molecular entity having an available ...

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1answer
40 views

Amount of Phenolphthalein required

We just had chemistry practical few days a go. The topic was strong acid-base titration. In which we have to find normality and concentration of $\ce{HCl}$. My teacher instruct me to add 2 drops of ...
1
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1answer
39 views

Nitration of Aromatic Compounds

I am told by Dr. Klein that in the nitration of benzene, hydrogen sulfate anion acts as the base and deprotonates the sigma complex. My question is why would the hydrogen sulfate anion be doing ...
8
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3answers
2k views

Why is magic acid a superacid?

The above is a representation of magic acid. The left part is the acid; the right part is the solvent. Why would this combination make for a particularly good acid? The left part looks like a ...
2
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0answers
18 views

Common etchant for Stainless Steel 304L and Titanium Grade 2

I need a common etchant for S.S. and $\ce{Ti}$. Right now I'm using: $\ce{HNO3 + 3HCl}$ - for S.S. 304L $5\%~\ce{HCl} + 6\%~\ce{HNO3} + 16\%~\ce{HF} + 74\%~\ce{H2O}$ - for $\ce{Ti}$ Is it possible ...
1
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2answers
61 views

Why can the lone pair not align with the phenyl moiety in 2,6-xylidine?

I am told that for this molecule, the amino group cannot line up in such a way that its p-orbital is parallel with respect to the p-orbitals of the carbons in the ring. I've looked for papers and ...
1
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2answers
31 views

Ammonia and hydroxide ion - Lewis basicity

Which is the stronger Lewis base, and why? I'm thinking that the answer is "it depends." With regard to the hydrogen proton, which hydroxide ion is obviously the stronger Lewis base. However, with ...
0
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2answers
22 views

Kb of hydride anion

I can't find any data about the Kb value of the hydride anion except that it's huge. Does anyone know what it is, or how I can characterize it? I know I can use electrochemical means but the only ...
0
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0answers
18 views

Concentration of hypochlorous acid and hypochlorite

Given a total chlorine concentration and pH, and pKa of HOCl, how would you find the concentration of OCl- and HOCl disinfectants? if the given total chlorine concentration =.1 M, pH of Cl is 8, and ...
2
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0answers
30 views

Boric Acid - Mechanism of Acidity

I was wondering how one could test the hypothesis that boric acid behaves not as a Bronsted acid but as a Lewis acid in that boric acid cleaves water molecules as to make hydrogen protons. rad ...
0
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0answers
14 views

Ligand strength - Coulombic effect and/or Electronegativities?

According to my teacher, these three Lewis bases generally decrease in strength in the following order: 1) Ammonia 2) Water 3) Hydroxide ion I agree. However, he argues that their ability to act as ...
3
votes
2answers
78 views

Why does ammonia react with water to produce hydroxide?

My question relates to dissolving $\ce{NH3}$ in water and how it produces $\ce{OH-}$ for the reaction $\ce{NH3 + H2O -> NH4+ + OH-}$? I know that the $\mathrm{p}K_b$ of $\ce{NH3}$ is $4.8$ and ...
1
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1answer
23 views

tap water and distilled water for electrolysis

my water electrolyzer which I've built using this pdf, produces less gas than I expected. In that file the author insists on using distilled water instead of tap water and I have used tap water. would ...
2
votes
1answer
373 views

How can I identify whether a substance is KOH or NaOH?

I've bought NaOH or 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 realized I've ...
2
votes
3answers
186 views

Why Does A Brønsted–Lowry Acid Accept Proton from Stronger Acid?

This is mechanism of Nitration of Benzene. In the first step, Nitric Acid (pKa = -1.4) accepts a proton from sulfuric acid which is stronger acid (pKa = -9). According to Brønsted-Lowry theory we ...
4
votes
1answer
90 views

Acid-base equilibrium of NH4CN

I'm having difficulties understanding this problem. We have in the problem that $K_a$ for $\ce{HCN} = 6.2\cdot10^{-10}$ and $K_b$ for $\ce{NH3} = 1.8\cdot10^{-5}$. Write chemical equations to ...
5
votes
1answer
96 views

Byproducts of the neutralisation of hydrochloric acid with sodium hydroxide

Given a 1M concentration of $\ce{HCL}$ and $\ce{NaOH}$ here are the pHs: pH of $\ce{HCL}$: 1 pH of $\ce{NaOH}$: 13-14 and of course water has a pH of 7. Here is a reaction that is most likely to ...
2
votes
2answers
104 views

Steric Hindrance and Bronsted Basicity

Does steric hindrance affect Bronsted basicity? I understand that basicity is a thermodynamic quality. Not a kinetic factor. So it doesn't matter if it takes a million years for the proton to reach ...
0
votes
3answers
50 views

Why cellphone batteries are still bad?

There are constantly new features in cellphones over the years, but it seems like batteries are not getting any better. Why is that?
1
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1answer
37 views

Can very dilute acids exposed to air become more concentrated as water evaporates?

If a very minute quantity spilled acid (e.g. $\ce{H2SO4}$, though the question would apply to other acids as well) is cleaned up with water (e.g. yielding a $0.0001~\mathrm{M}$ solution), and some of ...
0
votes
1answer
35 views

What is the chemistry of this household cleaning recipe?

What would be the product if baking soda and common salt and vinegar are added together?
2
votes
2answers
27 views

Find the color of the solution

The acid-base indicator methyl red has a $K_{a}$ = $1 \times 10^{-5}$. Its acidic form is red while its alkaline form is yellow. If methyl red is added in a colorless solution with a $pH = 7$, the ...
2
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3answers
35 views

What does the hydrolysis of a salt tell us about its basic/acidic character?

I'm curious to know how basicity and acidity arises when a salt or covalent compound is dissolved in water.
2
votes
2answers
167 views

Calculating pH of diprotic and amphoteric solutions

I am trying to understand this problem and its corresponding solution (complete solution not shown) First off, from the above one can see that the equilibrium constants when $\ce{H2ASO4-}$ ...
1
vote
1answer
63 views

How could household vinegar create a salt on car carpet?

I am not a chemist! My chemistry classes from my molecular biology undergrad are far behind me. But I think I created a salt, and I don't know how. Here is my mystery: I recently got some water in my ...
2
votes
1answer
72 views

Neutralization reaction

Question) Complete and balance each of the following molecular equations (in aqueous solution); include phase labels. Then, for each, write the net ionic equation. (A) $\ce{NH_3 + HNO_3 ->}$ My ...
7
votes
2answers
313 views

How much can the pH change through dilution?

Consider an acidic solution with Hydrogen ion concentration, $\ce{[H+]}$ of $10^{-5}\:\mathrm{M}$. Since $\:\mathrm{pH} = -\log \ce{[H+]}$ the $\:\mathrm{pH}$ of solution is $5$. Suppose we dilute ...
0
votes
2answers
54 views

Calculate the pH of acetic acid for a 0.02 M solution

We have a solution $\ce{CH3COOH}$ (acetic acid) with $c=0.02~\mathrm{mol/L}$ and the of acetic acid, $K_A = 1.8\cdot10^{-5}$. Calculate the $\mathrm{pH}$ of this solution. I tried everything ...
0
votes
3answers
73 views

Why is HSO4- shown as an example of a weak acid instead of HSO4?

I'm watching some (really awesome) chemistry courses, and I think I have a fairly decent handle on acids and bases (or maybe not, and I'm fooling myself). But the teacher just showed a table of ...
3
votes
1answer
43 views

Any possible additives to a drain cleaner I use as a source of NaOH?

It is in pellets. And the box says main ingredient $\ce{NaOH}$ at least $30\%$ (I hope it's more). The box also says "aluminium catalyst". My goal was to take these pellets and dissolve them in water ...
1
vote
0answers
35 views

Neutralisation of HCl with NaOH - generated heat and excess concentration [closed]

If you have $75\:\mathrm{mL}$ of $M(\ce{HCl}) = 4\:\mathrm{M}$ at $25\:\mathrm{^\circ C}$ and $100\:\mathrm{mL}$ of $M(\ce{NaOH})=5\:\mathrm{M}$ at $27\:\mathrm{^\circ C}$ with a final temperature ...
0
votes
1answer
29 views

How to create a buffer solution from NaOH and $\ce{CH3COOH}$?

In my chemistry book, they say that an approach to making a buffer solution of pH$=5.09$ is by adding an appropriate amount of strong base($0.052$ mol $\ce{NaOH}$) to $0.300L$ of $0.025 M$ ...
2
votes
1answer
38 views

Formation Constants; Lewis Acidity

I still distinctly remember reading about how Lewis acidity/basicity was characterized using kinetics. The reason given was that because formation constants are so large, these reactions are not ...
2
votes
1answer
71 views

Conversion of CO2 to methane

Suppose one could generate an enzyme with arbitrary conditions at the active site. What conditions would then be necessary to cause carbon from dissolved $\ce{CO2}$ in low $pH$ water to combine with ...
8
votes
2answers
285 views

The Acidity of Boric Acid

The “real way” boric acid behaves as an acid in water is first by acting as a Lewis acid (bottom reaction, in black). In fairness to the undergrads, I’d bet >25% of graduate students around the ...
4
votes
1answer
36 views

Differentiating between Titration, Buffer, diluted buffer, Deionized H₂O

I had a chemistry lab where we had to titrate three solutions with HCl, a buffer, a diluted buffer and deionized water. My partner and I didn't label the charts we made, so now I have to figure out ...
2
votes
2answers
100 views

Does H3O+ donate a H+ to Water?

Does the hydronium ion donate a proton to water? If the collision of 2 molecules of water can cause a proton to be transferred, does hydronium 'pass' a proton to water?
1
vote
2answers
42 views

Reconciling the units of pH calculation

As part of a simulation I am developing I have an acid in aqueous solution represented as a concentration field of mass density (units g/L) at various points in ...
2
votes
0answers
25 views

ice cream float - what causes it? [duplicate]

When you mix ice cream and a soft drink (like coke,) a reaction happens that creates a thick foam. I am assuming the foam id composed of carbon dioxide gas and milk curd, which is produced by the ...
1
vote
1answer
32 views

Which acids are created by the combination of a gas and water?

Which acids are created by the combination of a gas and water? I know that carbonic acid is created by combining carbon dioxide and water, but are there others? Is there a specific name for this ...
1
vote
1answer
32 views

Nitrogen Tetrafluoride, acid or base?

$\ce{NF4+}$ ion reacts with water as: $\ce{NF4+ + H2O -> NF3 + H2F+ + {1/2}O2}$. My question is, does $\ce{NF4+}$ serve as an acid or base in this reaction, and why? Thanks.
0
votes
1answer
28 views

pka explanation through empirical formula?

Suppose two compounds with, say, pka(1)=2.8 and pka(2)=3.2, and formulae $C_aH_bO_c=C_pO_q(OH)_r$ and $C_dH_eO_f=C_uO_v(OH)_w$, respectively, with given abcdef, pqruvw. Can we explain the above pka ...
1
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3answers
63 views

Why does an acid exist when dissolved in water?

Acid is a substance that releases $\ce{H+}$ ions when mixed with water But if it releases $\ce{H+}$ ions the acid will ultimately not exist. For e.g we take the acid $\ce{H2SO4}$. If we add water ...
1
vote
1answer
203 views

Why is Aluminium Chloride a Lewis Acid if it's an ionic compound?

In my textbook it says in the reaction $\ce{AlCl3 + Cl- -> AlCl4-}$, Aluminium Chloride ($\ce{AlCl3}$) has six valence electrons and accepts a lone pair from $\ce{Cl-}$, but wouldn't that mean the ...
2
votes
3answers
57 views

Which alpha Hydrogens are more acidic?

Why is the alpha hydrogen of a acetoacetic ester less acidic than the alpha hydrogen of 1,3 diketone ? I was under the impression that acetoacetic ester has more resonance structures so it more ...
1
vote
0answers
38 views

How to determine amount of CO₂ in soda water

I've got a problem in determining the amount of $\ce{CO2}$ in soda water. Basically, I have boiled some purified water to remove the dissolved gas. By using a SodaStream machine, I made carbonated ...
2
votes
3answers
403 views

Hydrochloric vs sulfuric acids, which are stronger acids?

Of my belief, sulfuric acid might be a little stronger than Hydrochloric acids. Because even though they both are strong acids, one mole of sulfuric acid produces two times as much hydro ions as one ...
0
votes
1answer
44 views

Which is more acidic? CO or CO2?

Q1)Which of the given compounds is most acidic? $\ce{CO}$ or $\ce{CO2}$ ? How to solve(explanation)? EDIT: Q2) $\ce{BeO}$ is amphoteric while $\ce{B2O3}$ is acidic - True/False?
1
vote
1answer
69 views

Separation of Binary mixture?

I will be given a binary mixture containing two unknown compounds(the mixture could be either liquid or solid- I don't know yet). The plan of the experiment is to identify the two compounds. So my ...
1
vote
1answer
63 views

Homoassociation and Acid Strength

I understand that the strength of HF differs significantly depending on the concentration. I understand the basic theory behind this - homoassociation - and stabilization of the highly negative charge ...
2
votes
1answer
84 views

What happens as an acid is mixed with Sodium Chlorite

I'm told that when Sodium Clorite $\ce{(NaClO2)}$ is mixed with an acid (in a water solution) it produces Chlorine Dioxide ($\ce{ClO2}$) which remains (mostly or partly) dissolved in water. I would ...