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Compound Interest
compoundchem.com · Personal blog · on HN since 2014
Compound Interest publishes chemistry infographics and short explainers on everyday topics like decaffeination, bread-making, book smell and bad science.
What HN saysHN commenters recommend it for its infographics and cite its coffee decaffeination guide when discussing solvents and methods.
36HN people shared it
14linked it in comments
37stories submitted
168story points
6 months agolast shared
2014people per year2026
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What HN people wrote when they linked it
thewanderer1983 · 2023-08-31
Another great one is Compound Interest.
https://www.compoundchem.com/infographics/
philipkglass · 2024-07-25
Benzene hasn't been used in decades. See this for information about solvent decaffeination:
https://www.compoundchem.com/2018/09/26/coffee-decaffeination/
Earlier this year dichloromethane was banned in the US for all but a handful of uses, so producers who used it in the recent past will not be able to any more:
https://www.epa.gov/newsreleases/biden-harris-administration-finalizes…
magicalhippo · 2024-02-27
Never had to train myself, always just liked them, and they don't taste particularly bitter.
So I had a hunch it was like cilantro, and seems there's indeed a genetic reason[1].
So fair enough, if they taste bitter I'll accept it's not a nice side dish.
[1]: https://www.compoundchem.com/2014/12/04/brusselssprouts/
esperent · 2023-08-26
> When interpreting electrons as particles, the atom is mostly empty
The Bohr planetary model, which I assume is what you're referring to, is equivalent to Newtonian mechanics. It's simple to understand and a good starting point for high schoolers. It's even still usable for certain types of calculations.
However, like Newtonian mechanics, at a deeper level and according to modern understanding, it's fundamentally wrong.
Instead we use the Schrodinger electron-cloud model. According to which the nucleus is not mostly empty.
It's not pedantic to discuss this, any more than it's pedantic to discuss why Newtonian mechanics is less accurate than relativity.
https://www.compoundchem.com/2016/10/13/atomicmodels/
aix1 · 2023-05-14
You're thinking of the method called '(Swiss) water decaffeination', which does indeed only use water. However, these also exist other methods, some of which do use solvents:
https://www.compoundchem.com/2018/09/26/coffee-decaffeination/
ChrisArchitect · 2021-07-31
Compound Chemical post and infographic where probably a bunch of this article was sourced from:
https://www.compoundchem.com/2021/07/27/tokyo2020/
sohkamyung · 2020-10-07
For those interested in a infographic on the chemistry of grapefruit, see [1]
[1] https://www.compoundchem.com/2014/03/07/why-does-grapefruit-interact-w…
totony · 2020-04-02
This [0] does not suggest that anything but ethanol/water and potentially some other volatile compounds are in the distillate. I'm not familiar with brewing and flavoring distilled spirits, but quite familiar with distillation and doubt that even oil would be in the distillate.
[1] suggests that tannins are present in the distillate, but I have not found a tannin that is volatile and [2] names one that isn't in beer
Flavor seems to be added after distillation from what i can see (and is potentially influenced by the volatile impurities)
[0] https://www.compoundchem.com/2016/06/08/vodka/
[1] https://vinepair.com/spirits-101/how-distilling-works/
mprovost · 2019-12-20
I think the parent comment was implying that jam can be healthy just because it uses whole fruit as an ingredient. The chemistry behind turning a mixture of fruit and sugar into something called jam is pretty well known - there has to be a certain ratio of sugar for it to "set". Usually this is 1:1.
I wrote my comment because I think that people are shocked when they actually see jam being made at home and how much sugar goes into a batch.
https://www.compoundchem.com/2014/09/22/what-makes-jam-set-the-chemist…
Sohcahtoa82 · 2019-08-19
> At what point does it become dangerous to continue to drink water ?
According to this page [0], the LD50 of water is 6 liters, so somewhere before that.
[0] https://www.compoundchem.com/2014/07/27/lethaldoses/
kabouseng · 2019-07-10
Don't eat spinach for iron, spinach is a very poor source of iron...[1] [multiple other sources you can google as well]
And vegetarians struggle quite a bit with getting proper dietary nutrition, not just with iron, but also Vitamin B12, Zinc, Omega-3 fatty acids, Vitamin D, Calcium, Protein and Riboflavin. So it is not quite just "simply" adjust your diet you lazy meat eater.
[1] https://www.compoundchem.com/2018/07/17/spinach/
Jamesbeam · 2026-04-23
Interesting paper.
But does it really matter how much caffeine is in a cup of coffee?
The LD50 for coffee is so high you can’t reach it via coffee cup consumption realistically.
https://www.compoundchem.com/2014/07/27/lethaldoses/
If you want to find the optimal caffeine intake for yourself while still enjoying coffee for the aroma and taste, you probably should switch from hot brewing, which basically forces you to drink a whole cup with an unknown amount of caffeine because of all the variables before it goes stale, to cold brewing.
As the cold state allows you to drink the beverage in as small quantities as you want over a longer period of time while keeping its taste for up to a few days.
Overall, this means finer control of the caffeine intake until you feel optimally caffeinated.
It’s cool to see scientific evidence, that we really can’t control the exact amount of caffeine in a cup of coffee, but what we for sure can control is our intake of that unknown amount and therefore lower or eliminate the side effects that come from taking in too much caffeine.
What I’d like to see is more research about if we possibly could grow coffee beans without any caffeine in them that provide the taste and aroma we enjoy in coffee, and then adding individual amounts of caffeine to the beverage externally.
Who knows, maybe instead of ordering cup size and aroma modifications from a barista, we also choose how much caffeine is in our cup to go in the future. It would for sure…
eggy · 2021-11-05
Ignorance was/is bliss for the pleasure. I don't smoke (never did, really), gamble (parents were rabid horse bettors), or drink anymore, so let's say it is one of a few vices I am keeping for the pure pleasure of it. At least I am not huffing gas, and I always liked when my Dad pulled in and filled the car up.
I did paintings conservation for over 3 years, and I developed sensitivities to the benzene family like toluene and xylene; a whiff would give me an instant migraine, and I usually didn't get headaches much at all. All new construction, even the so-called 'green' techniques, has a lot more VOCs or other compounds that gas out, deteriorate, and otherwise create a by-product, which is why I liked my old drafty house. I lost some energy efficiency, but always had significant air exchange and all the glues had gassed off decades ago. New construction lead to Radon becoming more of an issue as a result of airtight basements and living spaces for the sake of energy efficiency. My old house was on top of glacial moraine, so Radon is something to be concerned about, but if it doesn't accumulate in concentration it is not as much an issue. That and simply caulking cracks and holes in your basement to keep it from entering in quantity is the other thing you can do. Also the drafty house ensured it never accumulated upstairs. The fix for newer homes was to put a vent to the outside the basement after caulking, sort of mini-chimney of stainless steel tube. And the fact is that it…
brownbat · 2017-07-26
> potential dangers of every synthetic chemical
I wouldn't put too much importance on the synthetic / natural distinction.
Lead, tobacco, and various radioactive elements (uranium, radium, thorium, and radon) are all perfectly natural. If you were harmed by chemicals in the last century, it was probably one of them.
There are also thousands of lab-made chemicals that never make the news because they're just not harmful.
The UK-based non-profit Sense About Science has produced some literature trying to combat what they call "chemophobia," the fear of man-made chemicals:
http://www.compoundchem.com/2014/05/19/natural-vs-man-made-chemicals-d…
Scientific American has tried to debunk myths about synthetic chemicals as well:
https://blogs.scientificamerican.com/guest-blog/natural-vs-synthetic-c…
I mean, yeah, don't drink DDT. But don't try to make your drinking water "more natural" either, thank your city for treating it with a little bit of synthetic (and toxic in large doses) chlorine, and enjoy a day free of all-natural additives like cholera.