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Methanol splitting pattern

for methanol, are the splitting patterns 2 singlets or 1 singlet and 1 doublet. And does OH group in COOH always show a singlet pattern
tbro's user avatar
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0 votes
0 answers
7 views

Is there a pressure that ignites H2 and O2 at room temprature?

I can't seem to find much information other than about temperature and that oxyhydrogen is used for welding (the wiki page doesn't seem to say, but I assume the gases are stored separately). Any ...
user145206's user avatar
0 votes
0 answers
6 views

Electrophilic fluorination power: Select fluor vs NFSI

I want to fluorinate the methylene hydrogens between an aryl group and a phosponate ester. The reaction is similar(not identical) to this one: For some reason on the literature people are using very ...
raptorlane's user avatar
0 votes
0 answers
9 views

How can a Michaelis-Menten formalism be used when enzyme concentration isn't constant?

In ordinary MM kinetics, I understand that Vmax=k3*E0. Apparently, when the amount of enzyme is treated as a dynamic variable, the reaction may be described by d[P]/dt = (V'max[S][E])/(Km+[S]) What ...
user145205's user avatar
-2 votes
1 answer
18 views

why is 1 calorie 4.186 joules?

What is the experiment that shows 1 calorie is equivalent to 4.186 joules called? I found one mention of an experiment that attached a weight to a prop and the friction of the water causes the ...
Cameron Austin's user avatar
0 votes
1 answer
13 views

what off the shelf chemicals break the factory adhesive bonding paper gaskets to a steel plate in an automatic transmission?

The adhesive chemical is unknown. This part is constantly exposed to temperatures from -20F to 300F, and is submerged is transmission fluid. The exact steel that the gaskets are bonded to is unkown, ...
MIKE's user avatar
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0 votes
0 answers
13 views

Difference between polyethylene sulfonate and Nafion?

Nafion is a cation-exchange membrane that I would like to build a chlor-alkali cell, but unfortunately it's crazy expensive(and comes in ridiculously large sizes). Its functional group, the sulfonate ...
interestedperson's user avatar
-1 votes
0 answers
14 views

How are the standard reduction potential of galvanic cells qualitatively explained?

In a galvanic cell, the standard reduction potentials involving the two electrodes determines which way the electrons flow, and hence, the positive and negative terminals. Most sources I have referred ...
Naveen's user avatar
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-1 votes
1 answer
26 views

Does cobalt form square planar complexes?

So I came across a question where we were required to identify the possible central metal atom using the following clues. An aqueous solution of metal ion M1 reacts separately with reagents Q and R ...
Zoey's user avatar
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-1 votes
0 answers
9 views

Can directionally oriented unpoled Barium titanate nanoparticles piezoelectric response?

If a nanocomposite which has piezoelectric Ceramic Nanoparticles Oriented along One of its crystal directions, It is possible to enhance the piezoelectric response of the material?
Kavindu Lochana's user avatar
0 votes
0 answers
10 views

Reaction entropies of lithium-ion electrodes

I'm looking for lithium-ion electrode materials with good thermogalvanic properties for heat harvesting. As a sort of pre-screening effort, I am looking for information about the entropy change of ...
wawas007's user avatar
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0 answers
15 views

When we dissolve some compound, and there is a possibility of precipitation of 2 diff salts, then the one with lower Ksp will be precipitated?

I asked this question since I came across a statement from the topic removing temporary hardness through boiling that magnesium bicarbonate on boiling gives Mg(OH)2, Mg(OH)2 predominates over MgCO3 as ...
Avaneesh B's user avatar
-3 votes
0 answers
15 views

Phosphate buffer saline with different pH values

I would like to know with which reagent we can decrease the pH of the potassium phosphate buffer saline?
Nada's user avatar
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-1 votes
0 answers
17 views

Why does COMT methylate the 3-position hydroxyl group of norepinephrine?(metabolism of norepinephrine)

Why group 4 hydroxyl is not methylated? What is the differences between hydroxyl of meta and para for methylation?
Shab's user avatar
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4 votes
1 answer
359 views

Why do self cleaning windows use titanium dioxide (specifically in nanoparticle form)?

This was another AQA GCSE Chemistry past paper exam question my neighbour's daughter (16) has. It is not dated but our inability to find a markscheme makes us guess it is 2023 as that markscheme is ...
Judith Jones's user avatar
0 votes
0 answers
22 views

Why doesn't vapour pressure depend upon the amount of liquid?

I was reading about the Clausius-Clapeyron Equation, which is as follows: I was also reading about Vapour Pressure, when I learned this: The vapor pressure of a liquid does not depend on the amount ...
Adhway's user avatar
  • 111
0 votes
0 answers
15 views

What is the best alternative to dialysis?

What is the best alternative to dialysis? I want to "design" at a purely theoretical level an industrial installation for the purification of a recombinant protein and dialysis is not ...
Mike's user avatar
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-1 votes
0 answers
15 views

Does pressure of vapor state affect vapour pressure of its liquid phase when both are in equilibrium in closed container?

In a closed container there exist a equilibrium between pure liquid and gaseous mixture i.e (gaseous mixture is ideal gas and liquid follows all classical chemistry laws). Also vapour state is ...
MultiUniverseExplorer's user avatar
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0 answers
15 views

Alkali-rich glass with working range at room temperature

I understand that the glass transition temperature (above which it is considered a super-cooled liquid) is quite far below the liquidus of the corresponding crystalline mixture. In the paper, "...
user145034's user avatar
4 votes
2 answers
482 views

I left scented candles in a polypropylene container. How do I remove the smell?

I left scented candles in a polypropylene container, for weeks. How do I remove the smell? I don't know what else to try... I've tried: Hand wash with Dish Soap (multiple times) Hand wipe with ...
user24090727's user avatar
2 votes
0 answers
22 views

Solubility or reactivity of tantalum carbide and potassium polyselenides?

It is probably an unexplored system, but is there anything known about the low temperature thermodynamic equilibrium state of this? By 'tantalum carbide', I mean $\ce{TaC}$, and by potassium ...
Paul Kolk's user avatar
  • 256
-3 votes
0 answers
37 views

Information about Rankine scale [closed]

What is the use of the Rankine scale? Why cannot we use international units? Why is there need of such a unit? If we want we can also make new units. Why is not US using international system? It it ...
Himanshu kaushik's user avatar
1 vote
0 answers
27 views

Could a de-commissioned synthetic ammonia plant be adapted for use in removing CO2 from the atmosphere (DAC)?

I was prompted to ask this question by viewing a disused $\ce{NH3}$ plant in the harbour near where I live. Like many it functioned using a methane feedstock from a natural gas find off the coast. I ...
Edward Hogan's user avatar
1 vote
1 answer
31 views

Why is R₃P=O common but R₂Si=O rare?

I can understand why R₃N=O is 'rare' since for this double bond to form, Nitrogen would have to recruit a d-orbital like phosphorous does (the charge-separated model) but for N the d-orbitals aren't ...
ajk's user avatar
  • 41
-1 votes
1 answer
38 views

Derivation of form of rate laws

for a given reaction $A \rightarrow B+C$, I read in my book that the rate law has to be of the form $$ \frac{d[A]}{dt} = - k[A]^m $$ Can someone tell me (or point to some sources) on how we know the ...
Kryptic Coconut's user avatar
-2 votes
0 answers
18 views

Does Glycerol-sawdust mixture stick to the bottom when you heat it in a pot?

When glycerol and sawdust of a ratio 8:1 are heated in a high-pressure cooker on a hot plate at 120°C for 2 h, will the mixture stick to and blacken at the bottom of the cooker?
Vera Maria's user avatar
-1 votes
0 answers
30 views

Why is the boiling point of alcohols primary > secondary > tertiary? [duplicate]

If I have 1-butanol, 2-butanol, and 2-methyl-2-propanol, the boiling points of each are 117, 99, and 82 degrees Celsius, respectively. Why does that happen knowing that all of them have the same ...
omar waled's user avatar
-1 votes
0 answers
26 views

Thermodynamics class 11 neet [closed]

In chemistry point of view , for the questions which asking for maximum work done (particularly for expansion process), do we need to consider sign or we should consider only the magnitude? Be careful,...
Vishal's user avatar
  • 11
-2 votes
0 answers
16 views

For checking the species are isoelectronic or not..? [closed]

For checking species if they are isoelectronic or not , do we have to count the valence electrons of central atom or of all elements of that compound ... i have read this new approach in a book JD LEE
Harsh's user avatar
  • 1
0 votes
1 answer
59 views

How to draw -NHAc?

Looking online, I can't find a drawing of the structure since it always seems abbreviated. Can someone show me what -NHAc looks like?
rainbridge's user avatar
-1 votes
0 answers
29 views

Reaction Smarts for Secondary Amine and Carboxylic Acid

Does anyone have a good set of reaction smarts for forming a bond between a secondary amine and a carboxylic acid? The basic format is: ...
Karl's user avatar
  • 99
-1 votes
0 answers
16 views

Activation energy [duplicate]

Can a reaction have zero activation energy? This was an assertion reason question in an entrance examination and different teachers had different answers. Please say weather this statement is true or ...
Tryon Doge's user avatar
-2 votes
0 answers
33 views

Filtering out sugars from liquid dye solution best scalable solution

I extract dyes from organic produce ideally we just want the colour-causing pigment in the final product. I have been extracting with ethanol as sugar is meant to be less soluble in it. I then add a ...
T Ayton's user avatar
0 votes
0 answers
46 views

Comparison of oxygen and carbon-12 as standards for mass

While studying about the standards of atomic and molecular mass, I have learnt that while initially hydrogen was used as a standard of mass (its mass taken as unity), according to my book, oxygen was ...
Smarika Singh's user avatar
2 votes
1 answer
113 views

Wave function in Schrodinger's model

I am trying to wrap my head around the Schrodinger's quantum mechanical model of an atom. According to the NCERT$^1$, the Schrodinger's equation is given by: $$\hat{H}\Psi=E\Psi$$ where $\hat{H}$ is ...
Chem-geek0's user avatar
-2 votes
0 answers
52 views

How did they explain physical state in old molecular bond theories

Physical state of non-polar compounds is explained by Van der Waals forces which are caused by instantaneous dipoles caused by random motion/uncertainty of electrons. However, in theories like Valence ...
Grig-nerd-reagent's user avatar
1 vote
0 answers
70 views

Calculation of Reaction Extent as a Function of Pressure and Temperature: Issue with Activity-Based Approach

I'm working on modeling reactions involving combinations of hydrogen (H), nitrogen (N), and strontium (Sr) elements. I've obtained the temperature-dependent Gibbs free energy of formation, enthalpy, ...
David's user avatar
  • 11
-3 votes
0 answers
17 views

Experiment about electrochemically active surface area [closed]

I did an experiment where I changed multiple electrodes in a fuel cell and measured the surface area. I repeated the experiment with 4 of the same electrodes however the surface area calculated ...
user145131's user avatar
-4 votes
0 answers
27 views

What is the worst part about research in chemistry? [closed]

We are looking to improve the research workflow for chemists! When you do your research, what is the most painstaking/annoying part, in your opinion? Please be specific and give examples if you can. ...
Junhong Luo's user avatar
-5 votes
0 answers
30 views

Presence of super rare compound Copper Peroxide?

So I'm trying to make copper acetate, and in equal parts 5% acetic acid and 6% hydrogen peroxide (slightly les H2O2 since higher concentration), I put a piece of copper metal. Immediately there was ...
sk123's user avatar
  • 1
-1 votes
0 answers
32 views

Confused about free energy equation and entropy change

I'm confused about two equations and how they relate to each other. These are $\Delta S = \Delta Q/T$ and $\Delta G = \Delta H - T\Delta S$. To derive the Gibbs' free energy change for the universe ...
Ocean1's user avatar
  • 1
-3 votes
0 answers
20 views

why is process always reversible for the surrounding [closed]

It is said that a process may be reversible or irreversible for system but it is always reversible for surrounding. Why would that be true?
T J's user avatar
  • 15
-1 votes
0 answers
19 views

Understanding the relationship between Delta G and Kp, Kx and Kc

**Upon reading the chapter about equilibrium from my physical chemistry book, I was convinced that ΔG=−RTln(Kp)(1) and that Kp=Kx(P∑v)(2) where Kp is the equilibrium constant with respect to pressure ...
Kintoke 's user avatar
-3 votes
0 answers
35 views

Can a substance be both neutral and amphoteric [closed]

Oxides are generally classified as acidic, basic, amphoteric and neutral. The pH of water is 7 so it is neutral. But it also reacts with acids and bases so it is amphoteric. So can a substance be both ...
Krrish Gupta's user avatar
-1 votes
0 answers
36 views

Comparison of the basic strength of the following compounds - Methanamine, Ethanamine, Propan-2-amine

According to what I have learnt, the more the electron donating effect there is, the more will be the basic strength due to better stabilization of the conjugate acid. Also, the priority for inductive ...
Suhail Sahib's user avatar
-4 votes
2 answers
40 views

Ethanol Interactions

I would like to know if anyone is aware of any substance which, when it interactives with alcohol (ethanol), and is consumed, changes the taste of the alcohol (negatively) and/or induces sickness in ...
J Cunningham's user avatar
-4 votes
0 answers
23 views

amount of current produced by galvanic cell [closed]

in two separate galvanic cells , aluminum is used as the anode in one of the cells and sodium is used as anode for the other , given that they have nearky the same atomic mass ans equal amount of mass ...
omar waled's user avatar
3 votes
0 answers
28 views

Thermostability of Metal Carbonates and Nitrates

While studying in high school, I came across the following thermal decomposition reactions: $$\ce{Li2CO3 -> Li2O + CO2 }$$ $$\ce{MgCO3 -> MgO + CO2}$$ $$\ce{PbCO3 -> PbO + CO2}$$ $$\ce{Ag2CO3 ...
Arnav Ranka's user avatar
-3 votes
1 answer
47 views

Why is o used for hydroxy groups in IUPAC naming instead of saying 2-hydroxy

For this question, i marked compound II correct as 2-methylbenzaldehyde and got the question correct, but for compound I, i marked it wrong and suggested the name to be 2-hydroxybenzaldehyde. I got ...
Snehal Bhadani's user avatar
2 votes
1 answer
870 views

Ultraviolet Movie

What is the best material for a screen using an Ultra-violet light projector? I need a material/screen that can convert and reflect the UV light into a visible light to best look like a normal movie ...
Justintimeforfun's user avatar

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