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The image shows sulfuric acid right up front. I can't imagine why they no longer sell those to kids.

However, if you think about it then as long as you provide the proper MSDS data-sheets and get the right waivers signed, providing a one-stop-shop chemistry set for educators/parents makes perfect sense.




It's 1.0M sulfuric acid. Much less dangerous than the concentrated stuff.


For a point of reference, a charged car battery's acid is about 4 times as concentrated, and there's a lot more of it.


But that's not a safe reference point is it? Should kids be allowed to handle the acid in a car battery?


My feelings about that are mixed.

On one hand, I try myself to avoid car battery acid as much as possible. It's legitimately nasty stuff, housed in a device where common use can lead to explosive venting of the battery's contents.

On the other hand, knowing enough about the acid to develop a healthy respect for it is vital to just about everyone in the US. Almost no one I know does jump starts correctly, and a starter battery explosion can permanently blind people.

Everyone ought to learn how to deal with things that are everywhere that can kill or permanently disable someone. Lead-acid batteries are everywhere, including children's toys. Knowing how to deal with them is vital knowledge in this society.


Is there some particular way I should be jumping a car? I only do it every few years -- and normally end up referring to the manual in the glovebox. Am I missing something?


Yes. You should make the connections in this order: 1) dead battery, positive terminal 2) live battery, positive terminal 3) live battery, negative terminal 4) dead car, unpainted steel on engine block bolt/alternator housing/chassis/etc, as far from battery as practical. This works because the negative terminal of the battery is the chassis ground anyway.

When disconnecting, break the connections in reverse order.

Lead-acid batteries release hydrogen during discharge (and may vent it if the discharge is rapid), or from overcharging (water can electrolyze). So the live battery is likely releasing some, and the dead battery might be if it's actually damaged and not charging properly.

So making the final, sparking connection (or first disconnection) is safest using the negative/ground wire (no potential), on the dead vehicle (avoiding the definitely-discharging live battery), and some distance away from the dead battery (mostly aviding the possibly-outgassing dead battery). This minimizes your chance of the spark igniting a cloud of hydrogen gas and getting a fireball.

And now that you know why the order is what it is, you'll probably be able to remember it :-)


No, the manual should be correct.

The key is to attach the last negative clamp not to the car's negative battery post, but to a grounded metal object away from the battery. This prevents sparking near the battery that can ignite hydrogen around the battery and cause it to burst.


The sulfuric acid I provide in the kit is only 1.0 M (= 2.0 N). And the quantity is less than 1 fluid ounce.


And Carbon Tetra-chloride! I'm not sure why I would want it, but I know I am going to have it. Do want.


That's a very dangerous chemical. I'm not sure i'd want a kid having access to it. I don't think I'd want it in my house. I have no problem with 1 molar sulfuric acid.


What's so dangerous about an ounce of it? They used to make fire extinguishers out of glass bulbs of the stuff.


Yeah, but the lack of chlorine trifluoride is a deal breaker. ;/


googles.

Ooh, that's fun:

"The ability to surpass the oxidizing ability of oxygen leads to extreme corrosivity against oxide-containing materials often thought as incombustible. Chlorine trifluoride and gases like it have been reported to ignite sand, asbestos, and other highly fire-retardant materials."

"Exposure of larger amounts of chlorine trifluoride, as a liquid or as a gas, ignites tissue. The hydrolysis reaction with water is violent and exposure results in a thermal burn. The products of hydrolysis are mainly hydrofluoric acid and hydrochloric acid, usually released as steam or vapor due to the highly exothermic nature of the reaction."

HF scares the willies out of me, and this stuff burns you and then turns into HF. Lovely!

"Handling concerns, however, prevented its use. John D. Clark summarized the difficulties:"

"It is, of course, extremely toxic, but that's the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water — with which it reacts explosively. It can be kept in some of the ordinary structural metals — steel, copper, aluminum, etc. — because of the formation of a thin film of insoluble metal fluoride which protects the bulk of the metal, just as the invisible coat of oxide on aluminum keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes."


If you enjoy that sort of thing, check out "Things I Won't Work With" by Derek Lowe: http://pipeline.corante.com/archives/things_i_wont_work_with...

The FOOF entry is always amusing.


There's a new one! I absolutely love this set of posts, haven't seen something added in ages.



Any of the chemicals in the Heirloom Chemistry Set can be switched, before shipment, for any other. While carbon tetrachloride can be dangerous in large quantities and with long-term exposure if properly storage and used it can be as safe as any other chemical. No chemical is entirely safe if handled in an unsafe manner. All of the chemicals have QR codes on their labels that take smartphone users directly to each chemical's Safety Date Sheet.



Does the kit contain Methylamine? Red Phosphorus? Ergot alkaloids by chance?


PDF pp 2-3:

http://www.hms-beagle.com/PDFs/BenchMark_Legacy_Chemicals_Pl...

Any bio&|chem know what's likely to do singe eyebrows or suffocate?


Well potassium nitrate is a pretty strong oxidiser. Mill it with a pestle+mortar and mix it with icing sugar 1:1 by mass. Put 30-40g on some alu foil.

Setting fire to that will produce crap loads of smoke very quickly. I filled my entire garden up with smoke with one of them a couple of years ago.

Sure there are more in that list but that strikes me as the most obvious.


I was a chemistry nutcase in high school, and even I would draw the line at ergot.


I love rhetorical questions! No, no and no.


I don't get the chemistry of it, but the kit says it will also include ricin as some kind of safety measure.


> The image shows sulfuric acid right up front.

It also has sodium hydroxide, which is nastier (imo) than sulfuric acid.


You can buy nearly pure sodium hydroxide crystals in large canisters from the supermarket.


Well, you could a few years ago. I haven't seen in on shelves in my area for some time. It is still easy to come by at stores that sell soap making supplies, and bio-diesel making supplies.


I see Caustic soda and sodium hydroxide quite often.

I don't see borax. I'm in the UK, and I think there's some cancer concern about it.


Yeah, the sulfuric acid was just the first thing I noticed. Looking around that same picture shows a plethora of chemicals that can do nightmarish things to the human body.


Most chemicals can do nightmarish things to the human body. It depends on the dosage.

(Heck, even human bodies do nightmarish things to other human bodies.)


That's true, and this set is probably not going to be used by idiots.

I have a strong reaction to sodium hydroxide because I've seen the results of burns with it.


Even plain old water can easily kill you.


Correct! The worst is hydrogen monoxide poisoning!




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