My supervisor gave me a bunch of glassware to clean, among the other things there’s this round bottomed flash with the cap stuck, they have no clue what’s inside, I tried both gently heating the joint with a blow torch but it didn’t work, also I don’t want to heat it up too much because I don’t know what’s inside. I also tried cooling the cap but also didn’t work. I tried putting the whole thing in an ultrasound bath hoping the cap would pop off but didn’t work either. Suggestions are welcome.

I’m a senior in university, and I’m just now getting into research after a long time debating what I really want to do. I’ve joined a project at my school and while I enjoy lab work, I feel like most of the time I have absolutely no clue what I’m doing while everyone else is sure of themselves. Does anyone else feel like this?

I’m back in college after 5 years so I can’t remember what info should be on it. I should be able to either fit it in my large tote bag or in a binder and it should be color coded preferably. It’s allowed to be as detailed as possible.

I’m currently doing a school research project on the alkaline hydrolysis of PET to recover terephthalic acid (TPA).

My basic setup uses PET flakes, NaOH, an ethanol/water mixture, heating under reflux, followed by filtration, acidification to precipitate TPA, washing, drying, and finally a back-titration to estimate purity.

I’d like to hear from anyone who has
actually done PET alkaline hydrolysis in a lab. What were the biggest practical problems you ran into? what would you do differently if you repeated the experiment?

I’m mainly interested in practical laboratory experience.

Found this during a lab cleanout and I have absolutely no idea what it is. It has two very thin graduated capillary-like tubes, each marked from 0 to 30 cm, and it says “B. Braun Melsungen” and “E 7433” on it.

Any idea what this weird thing was used for?

Does anyone know what plastics are soluble and what equivalent the solvent is.
i need it for a experiment i want to run but i can't find any research on the matter

EG: Styrofoam in acetone

Title says it all. I have a mystery fabric claiming its cotton, which its not. Don't know what it is, I think its polyester, but it could be a poly cotton blend. Only thing I know for sure is its some kind of plastic fabric, because it melts instead of chars and acetone doesn't do anything to it. Best way I can think of figuring that out is seeing what melts it. Any chemicals that eat polyester and are fairly easy to get?

Back in eighth grade my chemistry teacher did a demonstration of this crazy chemical reaction between a piece of candy and a beaker of powder i don't remember the explanation, or what the powder was. But I remember him wearing these big gloves and using tongs to drop a circular piece of candy about the size of a Skittle into the beaker which was in the vent window box thing (I don't remember what that thing was called but it was a glass box built into the wall between the schools two chemistry labs it had a vent to pull out potentially toxic fumes) and the moment the candy touched the powder it started sparking and popping like a miniature firework it didn't last long maybe a minute or two before it died out and all that was left in the beaker was a non edible saline solution. I also remember the teacher saying that he couldn't redo the demonstration cause he only had a little of the chemical and needed enough for his other classes.

Is this wrong???

Google says it's a fungus Aspergillus niger which produces citric acid not any bacteria.

I am in my first year of biochemistry (graduation)

Doing it from a distant learning program

This is a book they provided.

Are there any women on Youtube who run channels independently showing practical chemistry experiments being done (e.g. NileRed). I hvae yet to find any such channels. In contrast, there are many men doing this on Youtube.

NileRed

Nurdrage

Doug's Lab

Cody's Lab

Apoptosis (https://www.youtube.com/@integral_chemistry)

Chemiolis

Amateur Chemistry

vibzz lab

Cranial Construction, Chemplayer, Scrap Science, Prussian Blue, Thoisoi2, NightHawkinLight, and many more. but these are all men.

There are some women who appear on the ACS Reactions channel, but that is not focused on synthesis/experiments as much and is not independent.

Is there any way to get ChemDraw for free?

I mean I know it's in equilibrium with atmospheric CO2 according to temperature and pressure. But I keep coming across sources like this one, that say that water left out overnight is absorbing CO2 and that's contributing to a change in taste. https://geekerhertz.com/article/the-science-explained-why-does-water-go-stale-overnight

This makes no sense to me because 1. The change in taste would be to become more sour if the water was becoming more acidic by basically spontaneously becoming carbonated overnight, and 2. My understanding of gas dissolution in water is that it's fairly quick, and no more gases are going to be dissolved in water after some hours than would have been dissolved within minutes, barring a big change in temperature or pressure (or partial pressure of CO2).

Am I wrong? Or is it the dozens of sources claiming to quote experts saying a glass of water left out overnight tastes funny because of absorbed CO2?

So thanks to u/PeterHaldCHEM, I am gonna try recalibrating the IKA-DT5 temperture probe, for that I am using a recirculating heater/chiller from Julabo, because I dont have any other accurate heating device, I ve also tried hold a max+-0,3K difference on the recalibration with the recirculating chiller which worked pretty good I think, this fixed my problem with the error 8, thanks alot for this :). Disclaimer: dont judge the improvisation

Anything you would like to publish? Volume 1 has not yet been published, you may therefore give any papers you write. If you are interested, ask for the template article.

This investigation is a fun side project—My main project is building a wooden boat on my channel, JungleRanch, but this battery build is a fun side project…)

I’ve been studying YouTube videos, papers, and earth battery concepts. Combining my engineering background with extensive Q&A with Gemini, I’ve settled on what I believe is the optimal DIY concentric galvanic cell design.

Anyone who have ideas knowledge and want to comment this post?

I have been studying several Youtube videos and other information some about earth batteries and in general galvanic cell.

Latest I have been communication with an AI (Gemini). Through different questions to this AI and combined my own engineering background, I have come a conclusion of the best DIY galvanic cell.

Key Design Conclusions:

A selection of the question to this AI;
- A Copper Zink cell  in moisture soil will decline rather rapid?
- What if using other material like aluminum?
- So if doing that how long time before needed to upgrade or change
- So if using Epsom salt will have better sustainability but less current?
- How thick should the aluminum or zinc folie be?
- Well the inner roll has less area. Wouldn’t it be better to have the zinc sheet as the outer layer?

Together we came to this Key Design Conclusions;

• Metals: Copper (Cathode) and Zinc (Anode) sheet metal provide the best balance of steady voltage and low internal resistance.
• Geometry: Zinc sheet forms the outer cylinder inside the tube wall to maximize anode surface area, reduce internal resistance, and increase sacrificial mass.
• Thickness: Minimum 0.5 mm metal sheet for structural integrity and long service life.
• Dimensions: At least 100 mm in length (preferably longer) to maximize active area.
• Container: 2-inch plastic conduit, PVC drain pipe, or clear vinyl/acrylic tubing with end caps for isolated cell units.
• Electrolyte: Epsom salt ($\text{MgSO}_4$) dissolved in water and held in saturated sand/peat moss to prevent aggressive pitting corrosion.
• Separator: Heavy-duty landscape fabric, felt weatherstripping, or heavy paper towel wrapping between the concentric metal layers.

Expected Lifespan (0.5 mm Zinc + Epsom Salt): 3 to 6 months of steady discharge per cell before anode maintenance or electrolyte replenishment is needed.

Does anyone have long-term test data on Epsom salt cell current density ($\text{mA/cm}^2$), or suggestions for optimizing the concentric spacing? Would love to hear your thoughts!

When I have built a test example I will log logging exact discharge curves using a ZKETECH (灼智) 4-wire electronic load tester connected to PC logging software to track precise voltage decay and capacity

I work in a pie shop, and I also have OCD, so almost everyday it’s a challenge for me.

After I was the aluminium pans and other containers with soap, I rinse them like 100 times cause I think that the soap will be toxic for people.

The owner tells me that just rinse it with water once or twice, and that I don’t need to rub it with my hands to remove the detergent completely, cause the oven(400-450 degree), will get rid of that. And since the pan will be there for ~20 min, this makes it even safer.

I just want to know, how big of a danger is it if I rinse the dishes once or twice, only until I can’t see the soap anymore, but I don’t rub them and I also can’t smell them cause it’s very busy sometimes.

Is this gonna be toxic for the people buying it?

Maybe it’s just my OCD talking, cause I asked the other people and they told me it’s okay since the oven has a very high temperature, but I also asked chatGPT and it told me that it’s not very concerning but also it’s not fine…

I have a pipette that when I draw water from my water samples, it doesn't form a concave meniscus as it is usual. It forms an asymmetrical meniscus like a / shape or convex shape. What's causing this? Organic contamination inside the pipette? I have washed it with detergent but nothing changed. What you do you recommend?

I am getting a tattoo and I am looking for some suggestions. I am looking for the artistic representations of gold and silver. I have looked up their valence electron configurations.

If anyone knows any interesting or cool representations for these elements that would be greatly appreciated.

Initial report - confirmation of chemical identity is needed

UPDATE: odd new detail reported

Building 18 - update

Aug. 29, 2026, 3:36 p.m.

Offices across campus have been responding to a reported hazardous material incident involving a single individual in a chemistry laboratory. The Institute became aware of the matter after the individual, a graduate student, self-reported to a local emergency room and claimed to have synthesized dimethyl mercury, a compound that is not authorized as part of their research program. Emerging information calls into question whether this compound was in fact synthesized. We are also able to disclose, with the student’s permission, that while the student remains under medical supervision, their initial blood test result, which was received today, shows no sign of exposure to mercury.

Building 18 remains closed at least through Sunday as specialized decontamination efforts continue out of an abundance of caution. This work will continue, and the building will remain closed until the work is complete.

https://emergency.mit.net/

Hello everyone, I found this old jars of homemade apricot jam in the bottom of my fridge, and it surprisingly smells like one of those acetone-based nail polish removers. As you might imagine, that's not a normal apricot smell, and I was wondering why. Plus, the fruits themselves don't smell like acetone, only their syrup dose for some reason, and there's no visible mold anywhere in the jar. After a quick Google search, I came to some conclusions that the calcium from the apricots turned into calcium acetate, which in turn somehow started turning into acetone, but i do not know if thats even possible. Can anyone explain what happened here? I'm very curious about this and thank you for your time.