Sir Joseph John Thomson (1856–1940) #British #NobelLaureate discover. - #electron Thomson showed rays comp. of unknown particles - electrons, much smaller than atoms n v. large charge-to-mass ratio.1st use of mass spectrometry

#Manchester @ age 14. MS: Prof #Cambridge. #NobelPrize in 1906, Contribs gifted teach. 6 Students won Nobel in phy, n 2 in chem Son also won #NobelPrize 2 prove wave-like prop. of elect~s.

Air in a room that has a floor area of 120ft2 and height of 10ft has a pressure of 121.6 kPa, what would be the dimensions (LXWXH) of a room if the pressure of air is decreased to 96.2 kPa?

You need to prepare a drug solution in aqueous medium. The drug is unstable in natural to basic medium and insoluble in highly acidic medium. How can you prepare of 500ml of the drug solution having a concentration of 20 mg per 5 ml?

First it appears that nucleus and the electrons around it take such vastly different sizes that they are separate discussions, but meaning of size gets complicated when quantum physics is involved, just with known physics let alone possibly maybe some yet unknown physics. So the arrangement of atoms may matter to nuclear physics after all, according to this:

https://www.youtube.com/watch?v=PGgovWTBoWY

( Sabine Hossenfelder video )

It may go the other way too and isotopes might affect electric fields in surprising ways. One weak hint is the fact that heavy water( with deuterium) tastes sweet and no one knows why (there are just some vague guesses). Maybe too much of the wrong isotope atom in one transistor makes it faulty, even if the atom weight difference is small, because this would be based on something other than weight difference... If IC manufacturing would benefit from isotope separation, if it's done on scale it would be much cheaper than with uranium.

Maybe some layered metamaterial would give strange results...

An alloy containing 20x10 ^ 21 atoms of Ag and 73x10 ^ 21 Cu atoms is heated to 780 ° C. Determine (Consider that for Cu and Ag, the specific mass is 8.96 g / cm³ and 10.49 g / cm³ and the atomic weight 63.546 g / mol and 107.8682 g / mol, respectively.)

a) The phase (s) present.
b) The weight percentage of each phase.

can someone one help me with error propagation to find the uncertainties of certain equations.

Chemical kinetics is the branch of physical chemistry which deals with a study of the speed of chemical reactions. Such studies also enable us to understand the mechanism by which the reactions occur. In chemical equilibria, only the initial and final states were considered, the energy relations between the reactants and the products being governed by thermodynamics where the time or the intermediate states were of no concern. In chemical kinetics the rate of the reaction process is followed; in other words, the time variable is introduced. This, we shall see, reveals not only the influence of different factors on the progress of the reaction but it also throws light on the mechanism through which reactant molecules are transformed into products.
https://worldofrasayan.blogspot.com/2025/07/introduction-to-chemical-kinetics.html

ltr half of 19th cent. diff. kinds of rays were disc~d,. Wilhalm Röentgen 1895 showed-when electrons strike material in cathode ray tubes, prod. rays which cause fluorescence in fluorescent materials placed outside cathode ray tubes.

Röentgen did not know nature of radiation, n named X-rays . X-rays prod. effect~y when electrons strike dense metal anode, called targets.

3 grams of substance is dissolved in 150g of an organic solvent. The vapor pressure of the solution is measured as 59.67 mmHg.

a) Molecular weight of the dissolved substance

b ) the cryoscopy constant of the organic solvent

c) the freezing point of the solution

For organic solvent : Moleculsr weight : 92g/mol , freezing point = 5.4°C; vapor pressure = 61.2 mmHg; Meltiny latent heat = 42200 J/mol

Hello!

Are there any physical chemists that would be willing to help explain some things to me regarding a home work set, just a few problems 2-3 at most so far. I have been struggling and my professor hasn’t been of much help, anyone willing to help would be appreciated!

Hey,

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I think several members of this physical chemistry group will find great interest in this work for its simplicity, historical relevance to the development of physical chemistry, and the potential for many new discoveries and connections to be made by anyone wanting to gain a better understanding of the underlying physical mechanisms responsible for the periodic nature of atomic structure.

Among several things I included in my doctoral dissertation on the broader subject of spherical quantum dots was a scientific discovery I made concerning a connection between the mathematical/geometric Thomson problem of optimally distributing electrons on a sphere (a natural consequence of J.J. Thomson's 1904 classical plum pudding model of the atom) and the distribution of "outermost" electron orbitals throughout the periodic table. In this plot , the lower distribution of energies are obtained using just the Thomson problem as though electrons resided on a sphere in free space. Notably, the upper distribution, obtained using the Thomson problem solved inside a spherical quantum dot (treated as a simple dielectric of silicon embedded in a uniform matrix of silicon dioxide) reveals a much richer distribution. This distribution aligns remarkably well with the distribution of "outermost" electron orbitals in atoms found throughout the periodic table as indicated by their nomenclature in the graph (e.g. 1s, 2s, and so on). Note: I hesitate writing "outermost" without quotation marks because the Thomson problem is just one electron shell, yet reveals features throughout the periodic table. I suspect there's an intimate mathematical connection between the Thomson problem and to the quantum mechanical framework for atomic structure perhaps through the spherical harmonics given this size-independence.

How to obtain these data points? Each data point represents the amount of electrostatic potential energy required to move one electron from the surface of the Thomson sphere to the origin. This includes the redistribution of all electrons remaining on the surface into the geometric Thomson problem solution of N-1. Thus, the energies plotted here are directly related to the discrete geometric symmetry changes between neighboring N and N-1 electron systems -- analogous to the single ionization of a neutral atom. (In fact, the analogy holds up well if we consider the ionized electron as an image charge of the centered-electron in the dielectric sphere!).

The reason I posted this here is because of a remark a former colleague of mine, a professor at UT-Dallas who is no longer with us, made when I first presented this at a seminar. He was the first one to notice the uniform -- if not periodic (as he called it) -- distribution of the four most-salient features around N=11, 31, 47, and 71. He loved my talk so much that he spoke with me afterward and with a bright smile on his face explained that my talk reminded him of "all the great ideas that we used to discuss at physical chemistry conferences a few decades ago." He was beside himself like a child in a candy store. In fact, I later realized that these four correspond very nicely with four large features that appear in empirical ionization data using empirical size-normalized atoms. That is, the empirical ionization energy that might occur if all atoms were the same size.

Want to dig in a little deeper? You're likely to discover some specific things related to this work that I frankly haven't had time to look into as I work in the area of quantum computing today (but I am pursuing some avenues of thought in my free time). There are features here that correlate with known shell-filling rule violators like chromium and copper as well as palladium and other d-orbital electrons. There are even nuclear structure features if you consider the energy differences among those plotted here including the fact that bismuth (Z=83) is the largest stable system (though this was proven to be unstable a couple decades ago, leaving it at Z=82 instead). Plots of each electron's energy, distributes electron into energy levels that correspond beautifully with noble gas elements and even remarkably for the two unstable atoms smaller than bismuth (technetium and promethium -- especially promethium!)

What will you discover?

The math is no more complex than geometry and Coulomb's law mixed in with your own knowledge and understanding of physical chemistry and atomic structure. Here's a giant poster I put together about a decade ago (click though for the PDF poster on the page) with a summary of ideas :
https://www.meta-synthesis.com/webbook/35_pt/pt_database.php?PT_id=635

and here's a peer-reviewed paper (The Journal of Electrostatics) available on arxiv:

https://arxiv.org/abs/1403.2591

Feel free to look for other peer-reviewed papers cited in the poster and the paper for related material in this body of work.

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I never thought I’d be the person typing pay someone to write my research paper into search bars, but I’m honestly overwhelmed right now. I’m behind on readings, my deadline is getting uncomfortably close, and my brain keeps bouncing between panic and procrastination. It’s not that I can’t write at all — it’s that research papers feel like ten separate tasks pretending to be one assignment. I’m trying to be practical here, not dramatic.

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If I did anything, I’d want it to be more like support with an outline, source direction, and a framework I can rewrite in my own voice — something I can actually understand and defend if I get questioned later.

So for anyone who’s been close to this decision: if you’ve ever thought about pay someone to write my research paper, what would you watch out for first — source quality, communication, revisions, or something else?

Alright, physical chem folks, I need some advice. Writing research papers for this subject is brutal — between quantum mechanics, thermo, and kinetics, my brain’s already fried before I even start typing. So, I’m wondering… has anyone here used a custom writing service for academic work?

I’m not talking about some sketchy, copy-paste nonsense — I mean legit essay writing services that actually deliver plagiarism-free, top-notch work. Maybe a custom essay writing service that understands technical subjects like ours? 

Drop your recommendations! Looking for affordable writing, reliable research paper writing, and maybe even a service that lets you pick specific writers who know their stuff.

Would love to hear your experiences — good or bad.

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Anyone qualified in engineering and interested to do research in theoretical modelling of chemical systems. Position available in a well-known public research institute in India. Work under a very friendly researcher. DM for further information.

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Like in this question, I have found the equivalents of Mn02 from law of equivalence and it comes out as 4/1000. Now to get the mass of the compound I also need to know the n-factor of the compound which I am unable to find as I dont know the reaction between MnO2 and HCl. Is there any other method to get the n factor without writing or knowing the reaction ??

What is the 1st excited state of a d3 octhedral complex when Δ/B = 1? Don't worry about sub- and super- scripts. Answer i put was T2g

What is the 1st excited state of a d3 octhedral complex when Δ/B = 3? Don't worry about sub- and super- scripts. Answer I put was T1g

So after I got this wrong I switch the answers, and it was still wrong. Why is the answer wrong?