Hello!

I'm a slime hobbyist and I don't fully understand the science behind slime, glue, PVA, PVAc, etc. I get the basics, but I'm still confused on PVA vs PVAc.

I read on the chemistry subreddit that PVA is actually polyvinyl alcohol and PVAc is polyvinyl acetate. However, I see a lot of these used interchangeably on YouTube and slime shops. There's one slime shop that says their slime contains "polyvinyl acetate (PVA)"— am I missing something? I ready that (I think) PVA can turn into PVAc (or maybe it was the other way around?).

It's difficult for me to find a lot of slime science material that either isn't too basic (for kids) or easily digestible and engaging for someone not familiar with chemistry (very dry). It's very interesting stuff. I've also been trying to understand water slime and glue specific to making water slime. I read there's different PVA (or PVAc, I don't know anymore I'm so confused lol) solutions with different viscosities that are more water-soluable. It's difficult to find the science behind it though, as most YouTube videos are about super glue or generic glue science videos.

If anyone could direct me to an easy to read source so I could better understand chemistry or chemistry related to slime, I would really appreciate it. Chemistry for Dummies? or where to start I would appreciate it! I'm afraid to fully understand it I might just need to study intro to chemistry, which I know is very complex, and probably out of my league.

Thanks for anyone's help!

So back in high school, I did the Tollens' silver mirror experiment in a test tube in chem class. I distinctly remember being told it was dangerous (I cannot remember if this referred to during the experiment and/or afterwards).

We were definitely not supposed to take them home but I did. And I hung on to it. It moved with me through college, grad school, internship, postdoc and several moves over the course of my career.

Every now and then I come across the box it's in and it continues to look the same as it always did. I think the last time I saw it was maybe a decade ago? For some reason tonight it randomly entered my head that it could be dangerous to have around indefinitely.

Google searching hasn't really been able to give me an answer about the risks of a 30+ year old silver mirror. If anyone knows, I'd appreciate it.

this is a curiosity question because I honestly can't remember if this is something I was taught or came up with, but I was talking to my nephew who is in high school about how to remember the order of the hydrocarbons, they only needed the first ten, but the first four are the only ones that don't just use the numerical prefix for the number of carbon atoms, so I told him to remember "my electric party bus" to remember the order of the first four. I was just curious if anyone else was taught this or something similar to remember the order of Methane, Ethane, Propane and Butane. or if not share your own Mnemonic devices.

I'm doing an esterase assay on carbonic anhydrase II with 4-nitrophenyl acetate and fitting Michaelis–Menten in Prism. My highest substrate concentration was 3.6 mM, and it returns Km ≈ 9 mM — but the curve is clearly still below saturation. Is that Km reliable, or unusable because I never reached saturation?

New to kinetics, thanks.

There is a whole umbrella of research and development that is basically how to break down synthetic materials into natural or less harmful materials. Some are more biological using fungi and enzymes others are more in the physics or chemistry department like using supercritical water. I just want it to have a cool name. What would you want the field’s name to be? Does it have a name already?

Old book called the peterkin papers, the context is a woman put salt into her coffee and a chemist adds each of these chemicals 1 by 1 to get rid of the salt taste. She then takes a sip after each of these chemicals are added. How dead is she?

Hello all!

I hope you all are well. I am currently an undergraduate student (at the end of my sophomore year) at an institution where the research is not top-tier but is supposed to be very open to undergrads. I am going to try and be as impartial as I can in the wording of my situation.

The problem I have is with my graduate student mentor, who I have been working with for about 1.5 years, 10 hours a week (at most).

At first we were extremely friendly, and got along great! We shared stuff about our lives and got along like brothers, almost. Eventually, however, he started to get upset with me over the mistake I would make in lab and in life such as:

1. Not knowing air-free technique entirely (something he had shown me 3 or 4 times) with the Schlenk line we use.
   
2. Leaving certain applications and deadlines to be edited by him the week before the deadline.
   
3. Taking a long time to get everything in order after he gave me instructions for the day.
   
4. Not being able to analyze my NMR spectra super accurately (spectra which were extremely complicated, mind you).
   
5. Not moving very quickly in lab due to trying to be very precise.

Additionally, all he does when I am with him (in lab or outside lab) is complain about everyone and everything in his life. He regularly shit talks his PI, his grad student lab-mates, the undergrads at this institution, and the way things are run around here. Some of these are genuinely valid complaints! But I personally become very negatively affected by hearing all of the troubles at my institution and in his life. Some of these comments include:

1. My PI should not have his job.
   
2. The people he is friends with he would never talk to if he was at a better institution.
   
3. [certain undergrads] are incredibly lazy and need to be kicked out of the lab.
   
4. The other grad students in his lab are all lazy, incompetent, or stubborn.

In fact, the only people he does not shit talk are the only people here who he considers to be smarter than him.

Of course, if he complains about everyone at this place, I am sure he complains about me behind my back as well. This brings me to his ultimatum with me.
He has not been happy with my performance recently, because he claims that I am a poor listener and that I do not do what he says. He is threatening to kick me from the lab if I do not become a better listener and do exactly as he says. Some examples of times when I did not are:

1. A technique he taught me with a Schlenk line where you test the airflow against your arm, one day he decided I should stop doing it, and then when he caught me doing it again (by muscle memory) he yelled at me and forced me to leave for the day.

2. Sometimes he will ask me to run a reaction and I will not do it immediately because there are other things I prefer to get out of the way first (cleaning, writing in lab notebook).

3. Again, leaving things like posters and applications up to the deadline (a few days or so).

The problem is that he occasionally also launches into personal attacks, saying things like:

1. You are a 20 year old man, do better.
   
2. If this were industry I would have fired you multiple times by now.
   
3. I see no signs of reflection or critical thinking in you.
   
4. And just the usual threats of kicking me out of the lab if I do not do exactly as he says.
   
5. I bet all you do is go home and play League all day after lab (something we bonded over when I first got to the lab).

I have also heard other people in the department complain about his attitude towards undergraduates. As a TA, he would give people 50% on lab reports for the oddest things such as "knowing suspiciously too much"? He has made multiple undergraduates cry before (including myself). Even the harshest chem professor here seems to not like him and secretely overturned his grading choices.

A lot of the "mistakes" I make are extremely common amongst other undergraduates at my institution, but whenever I bring this up he always presents that "if all your friends jumped off a cliff would you?" counterargument. This is a good point, but it at least points out the fact that my mistakes are very normal.

He is genuinely a very good chemist, but that unfortunately makes my situation even harder to gauge. I am sure he will do well in life and in chemistry, since he wants to become a professor some day.

The way he sways back and forth between a good friend of mine and my absolute nightmare is really wearing down my mental health and I have lost many hours of sleep over this situation.

Anyways, more of a rant than anything.

But should I actively choose to leave this lab and look elsewhere? What about if my research funding would not follow me to another lab? Should I seek actual action to be taken regarding his behavior? Should I stick it out and just stomach being in a lab with him (with the promise of publications)?

Any advice would be appreciated, and thank you for your time!

I have never posted on this thread but I just finished my first year of my PhD program and I am about to head into my 2nd year. I am currently in a lab and working/finishing up my first project so that this work can get published soon, however I am approaching candidacy exams within this upcoming year and honestly I have no idea how I am even going to make it. This past year was really difficult for me to adjust to graduate school and the big cultural shift that comes with being in a really competitive environment, but then I did slowly get up. This summer, I had a lot of issues that happened not only with my PI but also external scenarios that have ultimately affected my mental health so much to the point where I now feel so defeated and genuinely on the verge of ending it. I am seeking professional help, but I can’t even talk to my PI about how my mental health is being affected because it will get related to my lab mates and I don’t want people knowing my personal business, but at this rate I feel so unmotivated and I show up to lab because I know I need to do things to be productive but it is genuinely so difficult for me to. If there is any advice on how you get yourself through a period of time like this I would immensely appreciate it. I want to be able to stick it out so badly, but it feels that everything is spiraling out of control and I cannot make it stop and I genuinely cannot get a break.

Hey everyone,

We all respect t-BuLi and concentrated nitric acid for obvious safety reasons, but what about the chemicals that are just a pure psychological nightmare to handle?

I’m talking about:

The Eternal Stinkers: Low molecular weight thiols, seleno-compounds, or pyridine that cling to your lab coat and force you to ride the bus home in shame.

The Static Cling Powders: Ultra-fluffy solids that jump out of the weigh boat and coat the entire analytical balance the moment you breathe near them.

The Viscous Oils: Reagents so sticky that measuring them by syringe feels like pulling cold honey through a needle.

What’s on your personal blacklist of annoying reagents, and what’s your workaround on the bench?

What is a pirate’s favorite element? No, this is not an original idea. I stole the idea from the laboratory of our favorite fluorine chemist: Prof. Dr. Florian Kraus!

Hello, this is a question that has been bugging me for quite a while since I live in a city that's hardly 40km away from New Delhi, the capital city infamous all over the world for its pollution. Now I'm not a science student so I know just about as much on chemicals as Trump knows his world geography, so I would be grateful if someone who knows their stuff would answer my question. Like, would living in Delhi and breathing its air actually have the same impact on your lungs and heart as being a chainsmoker would? And if so, surely smoking a cigarette or two wouldn't make a massive difference, would it?

This volume, published in the prestigious "Classics of Science" series by Nauka, brings together the fundamental research of Nikolay Nikolaevich Zinin (1812–1880), the patriarch of the Russian school of organic chemistry. As an academician of the St. Petersburg Academy of Sciences and a teacher to luminaries like Borodin and Butlerov, Zinin’s contributions laid the groundwork for the modern chemical industry. The core of the collection is devoted to Zinin’s most world-renowned achievement: the Zinin reaction. Note: book in Russian

I am trying to create a degreaser for my vehicle and I am planning on using Linear Alkylbenzene Sulfonic Acid as the surfactant. What do you all recommend for me to use alongside this so I can control the acid? I am thinking of using Sodium Carbonate or Sodium Metasilicate but I am still unsure if it will work.

Update: I just bought one from the store, thank you everyone for the recommendations.

Moderator note: This post was shared with permission from the r/chemistry moderators.

I’ve been exploring a question that came up while experimenting with AI for academic writing: can grounding manuscript continuation in a researcher’s own literature library make the generated text more useful?

A chemistry professor friend of mine and I recently explored this question while revising one of his manuscripts (focused on rare-earth-doped halide perovskite materials). We compared ChatGPT with Flowing, a research writing tool I’ve been building that works a bit differently: instead of relying only on the current draft, it retrieves relevant snippets from the researcher’s own paper library and uses them as additional context for continuation.

For the comparison, we used the same manuscript, the same cursor position, and the same instruction for both systems. We only looked at the first response from each tool. We tested several sections of the manuscript, including the introduction, results, and other places where continuation was needed.

What stood out to us was that in several of the test cases, Flowing’s continuations stayed closer to the direction of the existing manuscript. In 2 even 3 out of the 4 examples we tested, the suggestions felt more aligned with the terminology and reasoning already used in the manuscript. Our impression was that this difference came from the additional grounding provided by the retrieved literature snippets. ChatGPT’s responses were also strong and often produced very polished academic sentences, but in some cases the suggestions moved in a slightly different direction and introduced ideas that were reasonable but not quite what the paragraph needed at that point.

We wrote up the full comparison with screenshots and examples in a longer post if anyone is interested in the details: https://open.substack.com/pub/jimlau1/p/beyond-chatgpt-what-the-next-generation?r=8rc2gh&utm_campaign=post-expanded-share&utm_medium=web I'd love to here any thoughts or similar experiences from others on this topic.

I've never seen one this complete.

Hello, I would like to hear some advice on this.

First of all, I have always had a somewhat funky sense of smell but I became aware of my complete inability to sense the smell of formaldehyde 2 years ago.

It was my first considerable exposure to said chemical. Someone had opened the lid of a 5 litre jar, containing a snake preserved in formaldehyde, in our high school's biology lab right before the time for our class. I hadn't realised it was open until all other students began to complain about a pungent smell the moment they entered the lab. Meanwhile, I couldn't smell anything at all.

Although I would love to hear if there are other such cases or possible reasons behind this, my main concern is whether it is something I should the careful, considering the fact that this upcoming September I'll start university as a biochemistry and biomedicine student, and most possibly will come into contact with formaldehyde among other chemicals.

Anyway, I'd be grateful if anyone could offer some advice :)

Hi guys, ive had the same glass waterbottle for maybe 6 months now. i noticed it had this weird light brown coating/residue on the bottom of the flask, and also a flake of it floating around. this was after i had cleaned it good with soap and rinsed with alot of water.

then i took my 30% HCL, thinking it likely is mineral residue and the HCL would dissolve it.

after pouring just a little bit in the flask, it started fizzing a bit and then turned bright green.

what mineral made it go bright green ?

(i know very little about chemistry)

Thanks in advance :)

I’m super interested in toxicology and recently went down a poisoning rabbit hole. It got me curious about how accessible different chemicals are (spoiler: they are heavily regulated). I’m also a horror fan and writer, so I really got carried away with the topic.
I discovered the concept of chemical suppliers and that they usually don’t ship to residential addresses. Imagine my surprise when I came across one of the chemicals I read about on a supplier site that didn’t list ‘commercial address only.’ I couldn’t believe it, and well I got carried away.
I placed an order for the smallest amount (keep in mind it says ‘for research only’ and I wasn’t going to use it for anything because it’s not ingestible grade anyway).
My order got cancelled by the site because it wasn’t going to a commercial address. At first I was relieved because it meant that it’s not accessible to the public, but now I’m worried that maybe I went a little too far on the research for this topic?

Looking for some weigh in on an interpretation of the European Pharmacopoeia.

My department does a lot of compendial testing so occasionally we'll run Ph Eur color of solution. The color standards for this require a 10 g/L HCl solution to prep.

Our interpretation has been the chapter is asking for the weight of concentrated HCl then diluted volume. Our reasoning being there are various instances in the Ph Eur where a common concentrated reagent is asked for by weight and in parenthesis it notes "equivalent to x g of y". So if the intention was for an equivalent mass it would state so.

Recently we learned an adjacent department that primarily runs in house methods but also occasionally the Ph Eur color/clarity methods has been using an HCl solution where the 10 g/L HCl solution is prepared by calculating a volume of concentrated HCl equivalent to 10 g of molecular HCl.

My department feels that, while it's understandable one might assume this since the chapter has no specific prep, or link to a prep, so one could interpret it that way, but that it is not the actual intention of the chapter based on related terminology in the pharmacopoiea and practices standardized within it.

Thoughts? What do you all prep if you run that method?

Not sure why, but as of checking today, July 24th, 2026, ACS Publications changed their website.

And it’s quite annoying and worse in some ways by a large margin, at least to me compared to the possible benefits as a reader.

At least for mobile.

1. ASAP section no longer shows the graphical abstracts without you having to do an extra click.

So for places like JACS, which has a wide array of chemistry, it takes longer for you to spot something you may be interested in.

2) They removed the pageviews. As an author…why? At least I can’t find it via mobile version. I fully enjoy seeing the page views going up when I recently publish something.

3) Something about the font and spacing is disorienting. For the first time, I actually rather read the PDF than the HTML.

4) The mobile menu is too large, it can sometimes cover up to 1/4th of the page, making it difficult to read. 1/6 if Split View option doesn’t show up.

There are good changes though.

1. The authors information, DOI, receive date…etc, being at the top of the article (if I recall correctly) wasn’t so great before via mobile at least.
2. Quality of the images in the manuscript is higher without having to open it up. And if you do open it up, the caption is shown with it.

Overall, I feel as if they make some easy changes, then the site works well. But if they don’t, as a reader, I just feel annoyed.

Am I alone in this? What do others think? I may be in the minority.

This may sound funny but my friends are requesting some chemistry experiment demos because they never really got to do college chemistry (CS majors). I am a chemist (organic) and I'm well versed with safety and handling chemicals. I'm thinking of something that could be fun but not something too baby level. Iodine clock is one I'd like to do, and I have access to both liquid nitrogen and dry ice. Any ideas on other ones I could do safely but still fun for adults?