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66 views

Does fluoroantimonic acid dissolve noble metals?

Hello,Does fluoroantimonic acid dissolve noble metals? Nernst equation suggests that platinum would require pH ≈ −20.1 to be dissolved, using Hammett acidity function as an extension of pH ...
2
votes
2answers
52 views

Loss of entropy and solvation energy in proteins

I am reading a chapter on protein stability. One section outlines the role of salt bridges or ion pairs in the stability of a protein. The excerpt goes as follows (italization added for emphasis): ...
-2
votes
0answers
39 views

difficulty of de-protonating a vinylic halide

I'm confused as to why the second elimination of a dihalide to form an alkyne is so much slower than the first. It seems like the H on one carbon an X on another carbon would still align their ...
-1
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0answers
30 views

How can one measure instantaneous ionisation ratio of a weak electrolyte?

Trying to get information about ionization ratio of weak electrolyte, led me to a few page with information about how to calculate it, but this will give me a static equilibrium answer. I'd like to ...
-1
votes
1answer
42 views

How to name radical

The name of biradical —CO—CH2–O—CH2–CO— is Oxybis (1-oxo-2,1-ethanediyl). Why is it wrong to write 1,2-ethanediyl instead of 2,1? Thanks in advance!
-1
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0answers
23 views

Why does nitric acid react with less reactive metals [duplicate]

So we are studying the acid base chapter and I came across these reaction: $$\ce{3Ag + 4HNO3 -> 3AgNO3 + NO + 2H2O}$$ My question is, how can $\ce{Ag}$ react with $\ce{HNO3}$ as it is lower than ...
0
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0answers
32 views

Finding the concentration of H+ in a polyprotic acid solution given the acid concentration [closed]

What is $[\ce{OH-}]$ in an $\pu{8.0 mol/L}$ aqueous solution of $\ce{H3PO4}$? From what I understand, this problem requires writing three subsequent chemical reactions that occur in order for $\ce{...
0
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0answers
51 views

Testing for lead in alcohol

I want to test for lead in alcohol rather than water. The reason for this is that I have many antique crystal decanters and flasks. Crystal is made with lead oxide (PbO) added to the glass. Normally ...
0
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0answers
36 views

How to find the temperature for when Kc = 1

The formulas I can use are $\Delta$G = H - T$\Delta$S, and $\Delta$G = $\Delta$G(s.t.d) + RTlnK I understand that when Kc is 1, the reaction is barely spontaneous and thus I can use the first formula ...
0
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2answers
45 views

Precipitation of equimolar amounts of chloride and bromide [duplicate]

I was just wondering about the following situation; if we had a solution containing 0.1M bromide and 0.1M chloride ions, and treated it with excess silver nitrate, what would happen and would ...
0
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0answers
33 views

What happens when you mix antimony pentachloride and hydrochloric acid? Will it form chloroantimonic acid? [duplicate]

Learning that fluoroantimonic acid, HSbF6, is produced by the reaction of antimony pentafluoride and hydrofluoric acid, I wondered if it would do the same for the chlorine. I have seen the other ...
6
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2answers
123 views

Why can two wavefunctions can be interchanged in integrals involving hermitian operators?

In many textbooks, it is said that because operators in QM are hermitian, we can write: $$\int \psi^*\hat{A}\phi\,\mathrm d\tau = \int\phi^*\hat{A}\psi\,\mathrm d\tau$$ An operator $\hat{A}$ is called ...
0
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0answers
49 views

Why is Ion Exchange Chromatography done in a column?

It seems like the idea of Ion Exchange Chromatography is to get a maximum amount of exposure of your gel to your solution. It seems like overhead stirring and a gel bed would be more likely to be ...
0
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0answers
27 views

Relationship between thermodynamics and steric hindrance in reaction outcomes?

I am investigating reactions with alkyl-substituted amines ($\ce{R} = \ce{Me}, \ce{Et}, \ce{^iPr}, \ce{^tBu}$) and a second reagent, in which product Z is formed. $\Delta G$ for all of these ...
0
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1answer
53 views

Haworth projection of Sucrose

I was searching for the Haworth projection of sucrose and I got this image from wikipedia (and much of the internet). (wikipedia link: https://en.m.wikipedia.org/wiki/Sucrose). But isn't it wrong!? ...
0
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0answers
14 views

how dilute should the solution be for a noticeable enough colligative property such as relative lowering in vapor pressure?

I was mixing soup powder with boiling water today and noticed the vapors coming from the water suddenly vanish; seemed like the powder being non volatile decreased the mole fraction of water in the ...
0
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0answers
23 views

Relationship of oxygen dissolved in water with bubble time and temperature

I'm using the Winkler method to calculate oxygen dissolved in water. This is at the temperatures 20, 30, 40, and $\pu{50 ^\circ{}C}$ and I bubbled a controlled amount of oxygen in through the reaction ...
0
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0answers
14 views

Decrease in electrical conductivity due to the increase in oxygen content

I am just wondering why there is increase in electrical conductivity of some materials with the decrease in oxygen, or vice versa. When Graphene oxide (which is an insulator) is reduced to rGO (...
0
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0answers
19 views

Why is the Heat capacity change of reaction different for ionization and electron gain?

Recently I read this statement in my book(ncert) that Electron gain enthalpy change and ionization enthalpy changes have different formulas $$ΔH_{eg}(T) = ΔH_{eg}(0k)+\int_0^TΔC_pdt$$ and for ...
0
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0answers
13 views

What is the protocol for esterification reaction between nanocellulose and tartaric acid?

I am trying to prepare nanocellulose esters via esterification with Tartaric acid. I know that the traditional method employs a strong acid such as sulfuric acid. What would the process look like in ...
0
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0answers
38 views

Should there be a better explanation on Van Der Waals force? [duplicate]

The explanation on how Van der Waals force forms is this: Van der Waals forces consist of induced, temporary dipoles between neighbouring molecules. These are caused by constantly shifting electron ...
-6
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1answer
56 views

Can someone explain this answer in detail? [closed]

The density of iron is $\pu{7.874 g/cm3}$ and its unit cell volume is $\pu{2.364E-23 cm3}$. These values indicate that there are: two Fe atoms per unit cell and the metal is body-centered cubic. I am ...
0
votes
1answer
133 views

Is there a molecule which has only lone pair electrons? [closed]

Lone pair electrons are "valence electrons that are not shared with another atom in a covalent bond" (Wikipedia). Is there a molecule which has only lone pair electrons?
2
votes
2answers
153 views

What does Partial charge means in Dipole Dipole forces [duplicate]

Dipole-dipole forces act between the molecules possessing permanent dipole. Ends of the dipoles possess “partial charges” and these charges are shown by Greek letter delta (δ). Partial charges are ...
0
votes
1answer
60 views

Racemization of hydrocarbon in presence of AlCl3

Our textbook mentioned that the compound in the diagram racemizes in presence of $\ce{AlCl3}$, but it didn't explain anything. Any help regarding the mechanism of the reaction would be appreciated.
2
votes
1answer
40 views

Filter out the SiO2 ultrafine particles from water solution to measure their total weight and size distribution?

The black soil sample mostly contains the organic matter, chalk and quartz. It is necessary to measure the relative weight of SiO2 particles that are 2.5 μm or less. To do that the organic matter and ...
1
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0answers
50 views

Is the wavelength of light generated through a chemical reaction independent?

The chemical reaction in question is the reaction between Luminol and hydrogen peroxide. Is the wavelength of light generated through this reaction dependent on the concentration of either reactant? I ...
5
votes
0answers
46 views

How are the energies of natural atomic orbitals calculated when they are, strictly speaking, not "meaningful" wavefunctions?

There are several programs that can calculate the "energies" of the natural atomic orbitals(NAO) that come from NBO analysis. However, I have several evidence that, unlike the energies of ...
5
votes
1answer
85 views

Why SCF procedure in Hartree-Fock doesn't keep returning the same coefficients?

In the context of Hartree-Fock theory, using Roothaan formalism, we write: FC=SCE where F is the matrix of the Fock operator, C are the coefficients to be used in the construction of the wave function ...
2
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0answers
46 views

major product formed in wurtz reaction in the given molecule[ 1,3-dibromo-2,2-di(1-bromomethyl)propane ]

This is the reactant molecule which undergoes wurtz reaction. All possible products are- What will be the most favorable in all of these? In my opinion that the last one should not be the one because ...
1
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0answers
47 views

What does “efficiency” refer to for a refrigerator?

A problem from my textbook mentions a refrigerator working with $35\,\%$ efficiency. I thought that in this case the coefficient of performance (COP) was used, specifically $Q_\mathrm{cold}/W,$ which ...
0
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0answers
5 views

Will my experimental setup for dielectric breakdown of membrane to form nanopore work? [migrated]

I am attempting to form a nanopore in a silicon nitride membrane using controlled dielectric breakdown. However, I want to do it with a budget < $500. I fear that the equipment I want to use will ...
2
votes
0answers
25 views

Chemical analysis of campholene nitrile

I have a problem. I am synthesizing an organic compound called campholene nitrile (2,2,3-trimethylcyclopent-3-en-1-ylacetonitrile). I need to analyze it. But there's a problem. I do not work for a ...
0
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1answer
43 views

Why does Phenylalanine to Tyrosine release H2O?

So I was reviewing Tyrosine and Phenylalanine metabolism (according to this video) and maybe I'm missing something but in the first step, 1: Oxygen atom reacts with Phenylalanine to make up Tyrosine, ...
-2
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0answers
71 views

Can molecules be pulled apart by magnetic fields?

If one were to have an molecule which two section, A and B, with section A being paramagnetic and B diamagnetic , and a magnetic field were to apply a force to the system, would there be a point if ...
-1
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0answers
22 views

Substitution of dihalo alkanes

Can I substitute 1,1-dichloropropane to get propane-1,1-diol? I'm just not sure if such a reaction would be correct.
-1
votes
1answer
19 views

Will concentration of sodium hydroxide affect the result of chicken feather hydrolyzate if i don't standardized it?

The title of the paper: Isolation and characterization of keratin from chicken feathers https://doi.org/10.1063/5.0002792 Here is the method: Keratin was isolated by dissolving 5g of chicken feather ...
2
votes
0answers
99 views

Why do we assume that the successive deprotonation of a polyprotic acid happens when only the previous deprotonation has reached equilibrium?

The steps for finding the concentration of the species at the equilibrium of polyprotic acid are as given in this book in section $10.16$ and illustrated on the next page. I have three questions, but ...
-2
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1answer
42 views

Why does $\mathrm{NO_3}$ have charge $1-$? [closed]

I'm given the following problem: Write the molecular equation for the reaction $\mathrm{Iron\;(III)\; Nitrate\; and\; Sodium \;Phosphate}$ I begin by attempting to determine the empirical formula of ...
1
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0answers
33 views

Hydrochloric acid from diaphragm electrolysis

I have a diaphragm electrolysis cell, which is made up of an outer container containing the cathode and a small terra cotta pot containing the anode. If sodium chloride solution is placed in the outer ...
-1
votes
1answer
38 views

Gases in the air [closed]

I was working on a question but I am unsure if I understood it properly. Maybe you can help me. In one experiment, Nitrogen was won during chemical reactions and filled into a baloon, and it weighs 2....
1
vote
0answers
14 views

Will a liquid-liquid emulsion and the separated emulsion have same volume?

Let's assume that there is no dispersed gas (bubbles). Not sure about dissolved gas; maybe you can tell me if that matters. Ordinary liquids (aqueous solution and biological oil). Surfactants are ...
1
vote
1answer
22 views

Help drying polyurethane sealent top coat

I've used a polyurethane water sealant coating for concrete that is called (vulkem 951 part A ) and it was supposed to mixed with part b the catalyst that starts the drying process but do to a ...
-1
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0answers
20 views

What quantity is one mole in the reaction in enthalpy change? [duplicate]

For example, I have a reaction: $H_2(g)+\frac{1}{2}O_2(g)→H_2O(l),𝛥H=-285.8 kJ mol^{-1}$ What does this "per mole" in the unit represent? What quantity is one mole?
0
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0answers
81 views

What are the wavefunctions for interacting electrons inside an atom?

The electron cloud for the single electron orbital $1s^1$ is radially symmetric in 3 dimensions. This is perhaps because of the probability distribution function (p.d.f.) $|\psi|^2 = ce^{-\frac{2r}{...
2
votes
2answers
204 views

Why do we need salt in a salt water battery?

I am having problems understanding why we do need salt added to the water to make this shown galvanic cell work. I understand that Zinc wants to dissolve into the electrolyte, resulting in $\ce{Zn^2+}$...
-1
votes
1answer
23 views

What is the effect of temperature on the enthalpy of reaction?

In the study of reaction mechanisms, enthalpy of formation for intermediate compounds at various temperatures is studied. I understand the reason to do that. How much (and what) effect can temperature ...
1
vote
1answer
121 views

Justification for using valence bond theory and molecular orbital theory together?

Elementary gen chem books will make the careful distinction between the two theories and then proceed to claim that chemists can use both to complement each other to explain the behavior of certain ...
1
vote
1answer
36 views

Why do radical inhibitors inhibit a reaction by creating a "more stable" radical, but for monohalogenation, we WANT to form the most stable radical?

According to my notes, radical inhibitors tend to turn a more reactive radical into a less reactive radical by making it more stable. For instance, the hydroquinone reacts with a radical species, ...
0
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0answers
27 views

What is the difference between PEF and PTF bioplastics?

I am trying to research single use plastics replacements, and wanted to explain how PEF and PTF are a good choice. Although as I am researching I can't find clear information about them, also how they ...

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