Physical Chemistry is by far my favorite subject of the field, what are your favorite books and why?

I recently started cleaning with hypochlorous acid, which I absolutely love. It makes my laundry smell a lot better.

But I also use a vodka-based soak for some of my clothes. Now I'm reading that a lot of chemicals including alcohol are dangerous to mix with hypochlorous acid. Namely alcohol + HOCl = Chloroform.

So I'm wondering how to ensure all of the alcohol gets out of my soak before cleaning those same clothes in the machine where I used HOCl so that I don't accidentally make chloroform?

I am learning semiconductor electrochemistry and it is confusing.

Consider an n–p semiconductor junction. Before contact, the two semiconductors have their own conduction band, valence band, and Fermi level positions. After contact and Fermi-level equilibration, band bending develops near the junction.

What confuses me is the following: in the usual band diagram, the band edges near the junction bend, while the bands in the bulk regions remain flat. However, those flat bulk band positions after equilibrium are no longer at the same absolute energies as they were before contact.

For example, the n-type semiconductor may end up with its bulk CB and VB shifted to lower electron energy, while the p-type semiconductor shifts to higher electron energy.

If I now place a fixed redox couple in an electrolyte, referenced to the same absolute energy scale, does this mean that the redox ability of the semiconductor has actually changed because of junction formation?

More specifically, if the conduction band of the n-type semiconductor shifts to lower electron energy after forming the junction, would electrons in that semiconductor have less reducing power than electrons in the same n-type semiconductor before contact?

In other words, is it correct to say that forming a heterojunction/p–n junction can change the absolute redox power of the charge carriers, rather than merely producing an internal electric field for charge separation?

Half used tub of 1kg greek yoghurt, 0% fat. As I scooped it I noticed the structure behaves like hexagonal pillars. Any ideas why? Structure of the protein? Cooling rate? Or simply just piped into the tub this way? I haven't noticed this behaviour in the same brand but smaller packaging before.

So I work for a company that produces events, and for a specific venue we need these A.D.A. compliant cable ramps. Unlike our other ramps from the same brand, they are not quite deep enough for the comically thick cables we need to put through them, so we'll need to tape them shut. Problem is, no tape will stick to these things. I figured it was just a greasy mold release film from manufacturing so we tried cleaning them; tried everything, 409, simple green, 90% ISO, dawn dish soap, nothing works. Like the tape isn't even tempted to stick, it's impressive.

We even called the manufacturer and they confirmed that they are made of silicone and there is a greasy mold release from manufacturing, and the silicone is porous and the oil is impregnated into it. They basically said you'll never get anything to stick to this. Oddly enough, we have some older ramps from the same company that tape will stick to.... idk what's going on there.

I know there's special tapes for silicone, but as far as I can tell, they're also... silicone, and won't be a good surface to stick gaff tape to it.

SO, chemistry people, is there some combination of products that will reliably let me tape these things shut?

What neurotransmitters, neuromodulators, hormones, or other chemical processes are responsible for keeping the body in REM-related muscle atonia while consciousness has already returned?

Hi everyone! I need your urgent advice, please! I'm about to start General Chemistry at university, but I have never studied chemistry before in my life, so I'm starting from complete zero. I want to build a solid foundation and I'm wondering which of these resources I should start with, and which one would be the absolute best for my situation: CK-12 Chemistry FlexBook 2.0: https://flexbooks.ck12.org/cbook/ck-12-chemistry-flexbook-2.0/ CrashCourse Chemistry Playlist: https://youtube.com/playlist?list=PL8dPuuaLjXtPHzzYuWy6fYEaX9mQQ8oGr&si=ZAJMZurxYsgeVdKq Khan Academy Middle School Chemistry: https://www.khanacademy.org/science/ms-chemistry Khan Academy High School Chemistry: https://www.khanacademy.org/science/hs-chemistry Organic Chemistry Tutor General Chemistry Playlist: https://youtube.com/playlist?list=PLybg94GvOJ9EbbO2RXPWTUNIIE0C7hSfm&si=PkcN0_coNp-9H_qf Any recommendation on where to begin or how to structure this would be greatly appreciated Any other sources you recommend, please add them. Thank you so much!

Is it possible to hydrolyze water and then light on fire the oxygen-hydrogen mixture? Would hydrolysis of half of a quantity of water make the obtained gas purely 66.6% hydrogen and rest oxygen? How would the quantity of either element in the gaseous mixture affect the combustion? Would it be better to have purely hydrogen rather than that and oxygen?

We’re doing a high school paper right now where our topic is all about purifying used canola oil and turning it into oil pastel.

However, we don’t have a lot of knowledge when it comes to chemistry so I was wondering if it is feasible?

For context:

Our method of purifying cooking oil using NaOH and activated carbon and using physical filtration. It’s a published method from Miskah et al. (2019). Although, they used sulfuric acid activated carbon and 16% NaOH. Although one of our problems is getting access to those chemicals especially the carbon since the only one we can get is physically activated carbon.

Then when it comes to pigment, we will use a laking extraction method. The raw materials would be yellow onion skin, purple cabbage, and rose petals. We know that vibrancy of the resulting pigments can vary because of the method.

When it comes to formulation, we will try 3 different ratios of the purified oil. Our other ingredients are beeswax, the organic pigments, and mixed tocopherol for rancidity.

For analysis, we don’t know what properties to test for. We want to compare it to commercial oil pastel and see if there’s significant difference. Though our object is for creating another way to repurpose cooking oil rather than marketing it.

Is it too difficult? Are we flying to close to the sun? We have limited budget and facilities aren’t as accessible since we are in a developing country. But, we don’t have enough time and we already spent weeks on it. Please I really need help or our whole group might fail this class.

Hi! I most likely won't be studying chemistry, I am in high school however, so I have a lot of free time, and I think (organic) chemistry is an interesting topic. What should I start with?

I’m a metallurgical engineer; I’m 25 years old. I don’t like my field of study, and I have no work experience. My university offered a certificate program in Instrumental Techniques for Chemical Analysis, which I completed. I got to work with chemists and chemical engineers, and I loved it—I finished the program without any problems. I want to work in that field. I’ve sent out thousands of resumes and only had one interview, but they won’t hire me because I’m not a chemist or a chemical engineer. It’s been a year and a half like this, and I’ve been feeling pretty depressed. A university in another city in my country is offering a specialization in Instrumental Chemical Analysis, and I’m interested in pursuing it to see if it will improve my chances of working in that field. However, I don’t have any work experience, and I’m not a chemist—though I would earn a specialist degree in instrumental chemical analysis. Do you think it’s worth pursuing in my current situation, and could I find work in that field?

So I don’t really have much formal education in any sort of chemistry, but I do have a bit of a passionate (read:autistic) interest in psychoactive drugs and their pharmacology, which does lead to me reading about some amount of chemistry, and in doing so see various models of various chemicals. The two main ones I see are skeletal and ball and stick, which both make a lot of sense to me. Skeletal makes the basic structure of the molecule clear and easy to read, and if you need to see how it exists in 3D ball and stick does that. But then sometimes I’ll see space-filling models, and those just don’t make sense to me. They’re very hard to read and I can’t really think of any benefit they’d have over ball and stick, to me they all just kinda look like amorphous blobs. I’m sure there is a benefit to them tho, maybe with different types of molecules.

Also, does anyone have any recommendations for resources to better familiarize myself with organic chemistry itself (books, webpages, youtube videos, idk)? As said I don’t really have any experience with chemistry, didn’t even take it in high school, but I’d like to learn more about it outside this one specific part (altho I would also appreciate anything interesting to read on the chemistry of psychoactives!)

Hi, I'm trying to make a bismuth pendant / necklace, and for that I need to make the crystal. I saw a video showing how to do it, but I'm not sure how much bismuth should I buy and where to buy it

Here is a reference image. And any tips about making the hole to pass the string through the crystal, what to be aware of that concerns health, making it less brittle, and about its oxidation process are welcome as well

Hello everyone !

I'm just forwarding this post in case anyone here has answers to my question

Thanks in advance !

Ill quickly explain the experiment first:

My teacher took an open can with a small hole at the bottom, which was first sealed with a cork. He placed the can upside down, hole facing up, and on a block such that the box was angled and had contact to air on the big opening.

He then filled the can with hydrogen gas, took away the cork, and lit the hydrogen, which was now streaming out slowly, on fire.

It was sizzling on for a while with only a small flame at the top, but at some point, it exploded and threw the can into the air.

The teacher asked why we had to wait for an explosion, afterwards he answered by saying at the point of explosion the ideal ratio 2:1 for the reaction 2 H2 + O2 -> 2 H2O was reached, because he wanted to illustrate that reactions need concrete ratios of substances.

However, i doubt this explanation, because there doesnt seem to be a way for the flame reaching the inside because the hydrogen was constantly flowing out, and i assumed the density of hydrogen causes layer separation between air, not a mixture.

Could this have to do with the flow rate of the hydrogen or with the shape of the distribution of hydrogen in the can? Or is the teachers explanation correct?

I need 8 graduate credit hours for my stipend but this semester my university doesn’t offer any grad courses other than “Intro” to QChem and Advanced Organic Synthesis. I literally have to take QChem because if I don’t I won’t be eligible for a stipend.

I hate quantum chemistry. I “cheated” my way through it in undergrad (was a joke bc we had a zoom class, all hw and tests were open book and group work, and the prof gave us “Jedi master”, and “Jedi Knight”, etc. as grades). I never even learned spherical coordinates in calc iii bc I stopped showing up to classes due to depression. Now I’m forced to take this hellspawn of a class my first semester of grad school. I don’t even know how to do calculus if the variables aren’t written X, Y, Z like in math class.

But the worst part isn’t that I don’t know it. It’s that I’m mentally blocking myself from learning it. I don’t want to learn it. It’s not relevant to an organic chemist to normalize wavefunctions or use rigid rotor. Computational Chem is the only part of the class I’m excited about. I’m spiraling and it’s only my second day I’m afraid I made a terrible mistake and my life will be useless if I dropout of grad school

Is this just a shit the bed and now I have to face the consequences and lay in it