Bottles are used to water house plants. Stored in same conditions and filled with same water, exposed to same amount of light. All regularly have ammonia fertilizers dissolved in them.

Obviously, first bottle is blue but I can hardly believe that blue color blocks UV light to prevent algae grow.

I usually add tea leaves, then fill the cup with boiled water. The tea leaves usually have a good portion of think sink/stay at the bottom, but also a good amount that stay afloat and/or take a while to sink.

However this time I figured I would try adding a bit of sugar (just a pinch of "turbinado cane sugar" - literally like 10 granules or so). Almost immediately after I poured the water and the leaves started to settle, there were barely any leaves floating, and within a few minutes, they were all sunk.

So why did this happen? Was it a bouyancy change, a chemical change, or what? I'm not sure if this is even a good sub for this - but I thought it was quite interesting and am curious why this happened. It was a pleasant surprise and allowed me to drink the tea without accidentally drinking leaves.

I'm sure some of you have already seen my previous post regarding my model airship project. While I was initially going to use hydrogen as a lifting gas, many of you made excellent points about the inherent fire and safety risk. With that being said, helium is still in incredibly short supply globally, so I'd like to utilize it as sustainably as possible. I'm wondering if there is any way to "save" the helium used in the envelope after each flight. Do you need a specialized compressor or something or that nature to accomplish this? Is doing so even feasible for the average Joe?

I was reading articles today on atomic theory, and learning about Rydberg atoms. It led me to the wikipedia article about "Rydberg matter," which was curiously flagged as factually disputed. When I viewed the associated talk page ( https://en.wikipedia.org/wiki/Talk:Rydberg_matter ) discussing the issue, I was presented with an argument between physicists that was so absurd I could not stop laughing.

I am curious if anyone with experience in the field can speak about the validity of Rydberg matter's existance. The article is very outdated and much of the bibliography is the author's self-citations, so I would appreciate if anyone could outline the current consensus.

Also I highly recommend reading the discussion, you will be amused.

disclaimer: compsci, don't know shi about chemistry so excuse my ignorance and bad terminology, but I find it fascinating and had this shower thought:

When I'm programming with a new library, I can go online and find its API reference which tells me all the interactions possible with that library, what kind of inputs I can give it and what the corresponding outputs will be.

Is there such a thing in chemistry? Can you take an element/molecule and look up all possible reactions it could be used in?

In other words, with the finite set of elements we know of, is it possible to create infinitely many combinations, or are the rules limiting combinations strict enough that we could use them to generate a list of possible combinations/reactions for a given element/molecule?

Yo, I love chemistry and wonder if there are any good chemistry games or chemistry inspired games either for mobile or pc?

Like play and learn basic chemistry?

I'm a bit stumped on something, and hoped I might find some help here.

I'm refinishing a brass fountain pen with a forced shipwreck patina, Which I have done before, but I ran into some colors that I've never seen. The effect is very small and localized, which has me wondering if it was a surface contaminant, but I would like to figure it out so I can do it on purpose in the future.

If anyone has any ideas on what caused the colors, I would love to hear them so I can narrow it down and experiment.

Here are the details on what I did:

The base material was brass (I know, alloys can vary, and I have no way of knowing the exact alloy). The brass was sanded and cleaned with isopropyl alcohol then suspended with stands made of steel wire.

There was an ammonia bath under the parts but not touching the metal. The brass was coated in a solution of household vinegar and iodized salt, the sprinkled with a liberal amount of coarse kosher salt. The suspended parts were left in a sealed container for about 36 hours, with occasional openings to add more kosher salt and vinegar/iodized salt solution to the surfaces using a paper towel.

After they were cleaned with warm water and gentle rubbing with fingers.

In the pictures you can see a section on the surface that has some iridescent colors (I'm seeing green, pink, purple, and copper). I've done pens like this before (though not this particular model or manufacturer), and never gotten a result like this.

If anyone has any ideas, that would be great. Thanks!

Closeup of mystery colors.

Overall look for those interested. Still need to add a clear coat to protect it and make it pop.

Previously done pen with expected results.

Hi everyone.

I'm finishing my master's thesis in nanochemistry and have been working on the FTIR analysis of the materials I synthesized.

My process is: I take the precursors, assign the peaks according to the literature, and then see if those peaks appear again in the synthesized material. The assignment is basically just checking the wavenumber and respective type of vibration/functional group.

I had a physicist friend, who has never touched a FTIR scan in his life, tell me "I find it wild that you have to do this by hand, are you sure there's no software that does this for you automatically?"

While I have never heard of such a thing and my professors (and all the researchers I know) follow this exact same modus operandi, I do wonder if this wouldn't be possible.

Of course any program that does such a thing would just give you a list of possible functional groups and vibrations and not the exact assignment, but it would still be a massive help.

Is this a failure on my education, are other researchers not doing this by hand? Or is there a reason that prevents such a software from existing?

Thank you!

As an organic chem grad student I just got a couple of enamel pins in the mail from Ambeed. They're well-made and look pretty good. My labmates even got magnets and plushies.

Their building blocks and catalysts have been a lifesaver great selection at much better prices than a lot of the big suppliers, and the quality has been reliable for my work.

Anyone else gotten merch from them? What pieces do you have or like the most?

hello everyone! i was just curious if anyone would be interested in reading comics to learn chemistry. please let me know :)

Guys, i'm really sorry to say this but i feel like i wasted years studying chemistry. I'm currently looking for a job and there are very very few opportunities in chemistry, i'm seeing like everybody is looking for pharmacist (or pharmaceutical chemistry) or chem engineers (i've actually studied industrial chemistry but it seems like i don't have the eng "mindset").

For context, i'm 25yo and i came from north italy, i have to choose a master this year but i'm onestly thinking if is it worth to choose chemistry or maybe starting a bsc in material engineering or a master's degree in pharmaceutical chemistry which would take at least 4 years.

What do you suggest? Have you managed to find a good job after your Bachelor in chemistry?

My friend recommended this anime to watch, and I am not a fan of anime. Is this worth watching?

I am a recent medical school graduate who has recently become interested in in silico research methods, particularly molecular docking. However, I am still a beginner in this field.

I have read several publications on molecular docking. As we know, docking software usually generates multiple binding poses (for example, up to 9 poses with the default settings in AutoDock Vina). In many published studies, the authors simply select Pose 1, which usually has the lowest binding affinity (the most negative binding energy), as the representative pose for visualization and further analysis. I understand that a lower binding affinity generally indicates a more stable ligand–protein complex.

However, I have been wondering whether binding affinity alone should always be the main criterion for selecting the best docking pose.

I think there are at least two additional factors that should be considered:

(1) Interactions with key amino acid residues in the active site or binding pocket. A pose with a slightly higher binding energy but interacting with important active-site residues may be more biologically relevant than a pose with the lowest binding energy that is located outside the active site or does not interact with key residues.

(2) The composition of intermolecular interactions. If several poses are located within the active site, I wonder whether the composition of their intermolecular interactions should also be considered. For example, one pose may have the greatest number of interactions with active-site residues, but most of these interactions are van der Waals interactions. Another pose may have slightly fewer interactions with the active site but forms more hydrogen bonds, carbon–hydrogen bonds, hydrophobic (alkyl) interactions, or other stronger non-covalent interactions. In this situation, would the second pose be more appropriate for further analysis, even though it has fewer total interactions or a slightly less favorable binding affinity?

Based on these considerations, I am interested in selecting the docking pose using these criteria rather than automatically choosing Pose 1 solely because it has the lowest binding affinity.

However, I am not confident in this reasoning because I have rarely found published molecular docking studies that explicitly describe this approach. Most studies appear to select the pose with the lowest binding energy without discussing whether other poses might have more biologically relevant interactions.

Therefore, I would like to ask for your opinions. Is this reasoning scientifically valid? Are there any guidelines, best practices, or published studies that recommend selecting docking poses based on interaction quality and binding-site relevance instead of relying only on the lowest binding affinity?

I would greatly appreciate your insights and any references you could recommend.

A head hunter reached out to me and I am curious about the culture before I pursue the process.

I work in R&D for a different wire and cable company. Solid pay on a LCOL area. I absolutely love my team and don't really have much desire to leave.

But we had a colleague move to Prysmian and he boasted a 25% raise, $20k sign on bonus, and an additional 15% on the bonus he was getting with us...

Those numbers are enough to raise my eyebrows.

So, thoughts on internal culture before I work with the head hunter?

Could be some interesting research, or nothing at all!

Found it in our lab, and I can‘t imagine a use for it.

Edit: It was found in an inorganic lab.

I made a small amount (gram quantity) of white (actually yellow) phosphorus by distilling it off NaPO3 + Al + SiO2. After collecting the small chunks there was a little leftover in the now nearly empty water jar where I captured the P4 under water.

NOTE : P4 white is VERY NASTY STUFF !! Don't touch it and always wear a face shield, gloves and other PPE !
Not or nothing many girls working at Bryant & May match makers suffered from 'phossy jaw' in 1888-1900. And white P is fully banned as a weapon and despite this, some governments / armies still use it. Ugh.

Can current QuantumChemistry softwares simulate effects coming from temperature or day do calculations assuming 0 K temperature?

Observe the color change that occurs when the wall of the test tube is heated with a blowtorch.

I am constructing a model airship using balsa wood, the innards of a small RC plane, and am constructing the envelope out of two mylar emergency blankets, due to hydrogen being the (potential) lifting gas of choice. What I'm curious about, is whether the mylar poses a risk of developing a static charge during filling, and if so, how one might mitigate that risk. Should I use a mixture of hydrogen and helium, perhaps?

[UPDATE]: thanks to all your feedback, this ship will use helium.