Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Things I Won't Work With: Peroxide Peroxides

pipeline.corante.com

Post reply on HN
Print view View original

41–50 of 56 posts

Re: Things I Won't Work With: Peroxide Peroxides

#41

Post by arethuza »

keithpeter wrote: post #29
refurb wrote: post #19

Earlier quoted context omitted.

I used to work at a pilot plant that did large scale synthesis of pharmaceuticals. The plant was a concrete structure with each reactor surrounded on three sides by two foot thick concrete walls. The interesting thing was that there was no outside wall to the building, just a woven steel curtain. If something did explode you wanted a path for the debris. On the outside of the building was a curved ramp, like a skateb…

My favourite chemical bunkers are the ones with a couple of feet deep gravel on the roof. So if there is an explosion, the resulting fire is smothered I assume.

Another Things I Won't Work With entry: "Sand Won't Save You This Time"

http://pipeline.corante.com/archives/2008/02/26/sand_wont_sa...

Re: Things I Won't Work With: Peroxide Peroxides

#42

Post by ChuckMcM »

Danieru wrote: post #25
ChuckMcM wrote: post #22

I was one of those kids that read that the original Bell jetpack used Hydrogen Peroxide with a silver catalyst for "fuel". I tried it on the peroxide I bought from the drug store and it didn't work. So I figured "oh it just needs to be more concentrated." My friend and I built a pretty crude still and about 10 gallons of 5% hydrogen peroxide. I don't know what the concentration was when we finished, but I do remember…

How? How!? How is it you always have cool and relevant stories!?

I chalk it up to curiosity on my part and survivor bias on the stories part. Folks who have known me for a long time know that I am a very curious person and I spend an inordinate amount of my spare time reading and "investigating" things (which my wife calls puttering). But there is also a bit of survivor bias here, it only seems like it is true because I don't have any stories to share on a lot of things here and elsewhere and don't. Oh and I'm "old", so I've got a lot of time between when I started doing crazy stunts and now, so even doing only one every couple of years I've got double the number of crazy stories than a "young" guy :-). That said, I'm sad that during my high school and college years the (late 70's early 80's) it was so much easier for me to explore things, whether it was the high school district's shared mainframe, or home made high concentration HOOH than it is today. No doubt if I were one of my own kids growing up in the 90's I would have been arrested and my parents assumed to be poor examples of responsible adults.

Re: Things I Won't Work With: Peroxide Peroxides

#43

Post by gregpilling »

ChuckMcM wrote: post #42
Danieru wrote: post #25

Earlier quoted context omitted.

How? How!? How is it you always have cool and relevant stories!?

I chalk it up to curiosity on my part and survivor bias on the stories part. Folks who have known me for a long time know that I am a very curious person and I spend an inordinate amount of my spare time reading and "investigating" things (which my wife calls puttering). But there is also a bit of survivor bias here, it only seems like it is true because I don't have any stories to share on a lot of things here and e…

Agree on the parent part. If I let my kids do anything remotely close to what I did as a kid, CPS would never let me see them again. I left in the morning and came back at dark, with no check in. I did experiments with things I learned in the Anarchists cookbook. Its amazing what you can blow up with household objects. You kids today have it easy blowing up stuff - just go on Youtube. In the early 80s you had to know someone to get the really bad somewhat illegible copy. My kids love watching Mythbusters when they blow things up. I wasn't sure whether to be happy or worried when my 8 year old asked for Polycarbonate blast shields. He was thinking of things he wanted to blow up, and how to do it. That made me worry. He wanted to do it safely and had given some thought to shield and remote triggering. That made me happy, i did not have the same focus on safety as a kid and burned my eyebrows off several times. As of today we have not done anything, he has got his attention on other projects and I am not going to bring it up.

TL:DR - typical 12 year old kid from 1982 would be labeled child Al Quaeda terror cell, parents would go to jail for 25 years.

Re: Things I Won't Work With: Peroxide Peroxides

#44

Post by dnautics »

nathannecro wrote: post #40
dnautics wrote: post #32

Earlier quoted context omitted.

it's actually got a lot of problems with it. Preferring strong bonds to weak ones is enthalpy . Entropy is (roughly) "preferring to make m product molecules over n molecules when m > n because the combinatorics of their positions is bigger" Energy is the total sum of the Entropic and Enthalpic components. (entropy takes a negative sign because more entropy is preferred; less enthalpy is preferred) The text also doesn…

You're certainly correct. I was just attempting to keep it simple.

yeah, I'm usually pretty good at explaining things simply, but none of the explanations here are making me happy, and I can't come up with a good explanation that encapsulates my intuition. Perhaps that means that I don't actually understand it very well myself.

Re: Things I Won't Work With: Peroxide Peroxides

#45

Post by ajb »

chrisbennet wrote: post #36

How to Blow Up Your Kitchen With Hydrogen Peroxide. A few years ago, upon returning home after work, my my wife told me that her mother had blown blown up her kitchen but that she was OK. (My late mother-in-law was a wonderful person BTW.) I can be prone to inattention when my wife speaks to me but this, this got my attention. :-) My mother in law was an antique dealer. To restore/bleach old china, she would put some…

That is really cool.

Any chemists care to comment on why the peroxide would explode in the microwave but not the oven?

Re: Things I Won't Work With: Peroxide Peroxides

#46

Post by [deleted] »

ajb wrote: post #45
chrisbennet wrote: post #36

How to Blow Up Your Kitchen With Hydrogen Peroxide. A few years ago, upon returning home after work, my my wife told me that her mother had blown blown up her kitchen but that she was OK. (My late mother-in-law was a wonderful person BTW.) I can be prone to inattention when my wife speaks to me but this, this got my attention. :-) My mother in law was an antique dealer. To restore/bleach old china, she would put some…

That is really cool. Any chemists care to comment on why the peroxide would explode in the microwave but not the oven?

[deleted]

Re: Things I Won't Work With: Peroxide Peroxides

#47

Post by CamperBob2 »

jerf wrote: post #4
idlewords wrote: post #2

This is a wonderful series that (rightfully) gets posted here a lot. I'd like to point out that the author's blog is also worth digging into for interesting and insightful posts about the modern pharmaceutical industry. For example: http://pipeline.corante.com/archives/2012/03/08/erooms_law.p... (how knowing more has actually made us worse at finding effective drugs).

Indeed. Be sure to click through: http://pipeline.corante.com/archives/things_i_wont_work_with...

This is very bad advice if you have anything else you need to do today.

Re: Things I Won't Work With: Peroxide Peroxides

#48

Post by avmich »

I wonder why the author is so caustic in regard to hydrogen peroxide.

Here - http://yarchive.net/space/rocket/fuels/peroxide.html - second message mentions Clark's "Ignition!" facts, and in first Henry Spencer states:

While there are some storage headaches -- the stuff decomposes slowly no matter what you do, so you must provide for tank venting -- otherwise peroxide is much easier and safer to handle. Its bad reputation is half outright myth and half the result of 1940s experience with seriously impure peroxide. To quote a friend, a rocket-propulsion professional, who investigated the matter as part of a study some years ago:

"As far as we could find out, the stories about problems with peroxide were just that, stories... Peroxide, now, seems to only very rarely do anything exciting, at all. And, even then, it seems to never do many of the things attributed to it in the stories."

Of course hydrogen peroxide can be dangerous - relatively recent explosion in Sweden (peroxidepropulsion.com) reminds us about that. At the same time significant volumes of it with more than 70% concentration are routinely used - so a chemist can calibrate the feeling.

Re: Things I Won't Work With: Peroxide Peroxides

#49

Post by CamperBob2 »

dnautics wrote: post #33
IgorPartola wrote: post #17

Earlier quoted context omitted.

I will attempt at conveying my simplistic understanding of it (physics major here): electrons are negative, protons are positive. Electrons want to be matched with protons. Two atoms can form a strong bond if they have just enough electrons to bond them but not enough to repel each other. Oxygen can bond to oxygen via a double covalent bond ( http://www.chemguide.co.uk/atoms/bonding/doublebonds.html ) but it has too…

Urg, O2 is actually a very bad example, because it's actually 'O-O' (where the ticks are radicals), this is called "triplet" oxygen. In the ground state it's a single bonded O2 with two free, unpaired electrons. There is "singlet" oxygen which is typically depicted as O=O, but it's actually O triple-bond O with two antibonding electrons that negate one of the 'triple' bonds which makes it effectively O=O but very dif…

If the OP asks about Newton's laws, and the parent responds with a brief summary of F=ma and friends, what good does it do to launch into a discourse about how all that stuff is totally wrong in the context of Lorentzian spacetime?

99% of physics and chemistry education consists of learning that whatever they taught you last semester wasn't quite right.

Re: Things I Won't Work With: Peroxide Peroxides

#50

Post by refurb »

avmich wrote: post #48

I wonder why the author is so caustic in regard to hydrogen peroxide. Here - http://yarchive.net/space/rocket/fuels/peroxide.html - second message mentions Clark's "Ignition!" facts, and in first Henry Spencer states: While there are some storage headaches -- the stuff decomposes slowly no matter what you do, so you must provide for tank venting -- otherwise peroxide is much easier and safer to handle. Its bad reputa…

As a former-chemist, I can attest that oxidizers in general are pretty concerning.

You are correct that hydrogen peroxide (even up to 70%) is pretty safe by itself, but a chemist like Derek Lowe would use hydrogen peroxide in a reaction. Since he's an organic chemist, nearly every reaction is going to involve adding that oxidizer to a reducing agent (almost every organic molecule out there). When you add an oxidizer to a reducing agent, you're creating an unstable mixture that would love to explode. Just because it hasn't exploded on people in the past, doesn't mean it won't in the future.

I can remember doing some really stupid things when I was in grad school. I had a create pure m-CPBA [1] for a reaction (great! an oxidizer and reducing agent all in one molecule!!). Thinking I was smart, I purified a a lot of it, like 20 g (smart folks only purify what they need, like 1 or 2 g). To make sure it was dry I put it on a vacuum pump and then heated the flask with a heat gun. Nothing happened, but looking back I was dam lucky it didn't explode. If it had, I likely would have been seriously injured.

[1] http://en.wikipedia.org/wiki/Meta-Chloroperoxybenzoic_acid

Post reply on HN