Chemistry Help

[EJDeBrun]

So I need some help in my WIP. I'm terrible at chemistry, but I need some good ideas on how to make a home made, napalm-like bomb. Molotav cocktail. Something along that nature. If anyone could lend me their knowledge, I would much appreciate it!

Also if anyone has a really good idea of how chemist test for chemicals or refine things, that would also help! They have access to glass, water and contained fires.

Context: Oceanic planet. The alien natives have battery technology, I'm considering sodium-sulfur. There are also chemical powders, but I'm not sure which ones would be best to use. One of those "powders" could be forms of salt or sugars.

The chemical mix will be contained in glass and flung at high speeds to shatter upon targets.

I'm sorry if this isn't very clear! All help and ideas appreciated! Thanks in advance!

 

[Locrian]

Biochemist here! Not sure if I can answer the first bit without ending up on a watch list, so I won't.

Testing for chemicals depends on what you are looking and how much. With no special reagents or equipment, it is pretty difficult to accurately identify or quantify anything. In my old lab We used to use a GC-MS on a broad scan mode to give intelligent guesses what levels of different organic substances were present, then would do GC-QQQ on specific programs and methods to quantify the ones we thought were there. Now I do on-site testing with a drop test kit; about 30 different bottles of indicators and buffers and a compact photometer. You might do XRF to identify inorganics. Not sure exactly on what you have available, but Analytical Chemistry is pretty hard to do in a cave with a box of scraps. I cringe when listening to some Sherlock Holmes radio plays where he claims some thing is arsenic beyond a shadow of a doubt because it does a certain thing with sulphuric acid, because a lot of other things do that too and there are a huge number of false positives.

 

[EJDeBrun]

Biochemist here! Not sure if I can answer the first bit without ending up on a watch list, so I won't.

Testing for chemicals depends on what you are looking and how much. With no special reagents or equipment, it is pretty difficult to accurately identify or quantify anything. In my old lab We used to use a GC-MS on a broad scan mode to give intelligent guesses what levels of different organic substances were present, then would do GC-QQQ on specific programs and methods to quantify the ones we thought were there. Now I do on-site testing with a drop test kit; about 30 different bottles of indicators and buffers and a compact photometer. You might do XRF to identify inorganics. Not sure exactly on what you have available, but Analytical Chemistry is pretty hard to do in a cave with a box of scraps. I cringe when listening to some Sherlock Holmes radio plays where he claims some thing is arsenic beyond a shadow of a doubt because it does a certain thing with sulphuric acid, because a lot of other things do that too and there are a huge number of false positives.

That's actually quite useful.

So basically we can assume that finding out what exactly is chemically available would be hard.

Hm. So that makes this a really difficult challenge to produce some kind of viable weapon with the objects at hand. I'll dig deeper. (I'm sure I've already been put on the watch list several times)

Thanks for the help!

 

[EJDeBrun]

Would putting things on fire help? I know different elements have different flames. That could at least isolate the types of chemicals used in something like a battery right?

 

[Cathbad]

@Locrian goes on the "He dissed Sherlock Holmes!!" list. check.

 

[Mike Donoghue]

So I need some help in my WIP. I'm terrible at chemistry, but I need some good ideas on how to make a home made, napalm-like bomb. Molotav cocktail. Something along that nature. If anyone could lend me their knowledge, I would much appreciate it!

Also if anyone has a really good idea of how chemist test for chemicals or refine things, that would also help! They have access to glass, water and contained fires.

Context: Oceanic planet. The alien natives have battery technology, I'm considering sodium-sulfur. There are also chemical powders, but I'm not sure which ones would be best to use. One of those "powders" could be forms of salt or sugars.

The chemical mix will be contained in glass and flung at high speeds to shatter upon targets.

I'm sorry if this isn't very clear! All help and ideas appreciated! Thanks in advance!

My chemistry is good, but not great, so here it goes:

It sounds like your world is relatively primitive, so Ammonium Nitrate + Fuel Oil, AKA, the infamous "ANFO" explosive, might be a good one. Ammonium Nitrate mines are found in nature, although they are not common. There are plenty of detailed websites on it as it is a widely used industrial explosive. I think it requires a smaller explosive to initiate, though. Black powder could work. That could be placed somewhere at the top of the jar with a piece of flint and steel so that the impact creates the sparks needed to ignite the black powder. You might also be able to use a capacitor's discharge in place of the flint in generating the sparks.

As for napalm, that is gasoline, kerosene, or really any other liquid petroleum that has been turned into a gel. I don't know what could pass for a gelling agent.

 

[Foxbat]

Maybe you could just adapt the Greek Fire method? It uses a siphon technique rather than just throwing and was used a lot at sea. The article mentions a few possible sources of this compound.
Greek fire - Wikipedia

As for the chemicals themselves, if it's an imaginary world then why not come up with a few imaginary chemicals with names that hint to the reader what they do? That saves you worrying about real-time chemistry? As for getting the chemicals in the first place - trace elements distilled from the ocean (or perhaps petroleum based from rotting sea vegetation?) As for a gelling agent, how about a Carrageenan? Carrageenan - Wikipedia

 

[Danny McG]

Agenothree

 

[Brian G Turner]

Molotav cocktail ... The chemical mix will be contained in glass and flung at high speeds to shatter upon targets.

You're basically talking about a petrol bomb, not a proper explosive - all that's required is refined oil and a burning rag to ignite it. No real chemistry required. If there's no oil refinement, then something like fractional distillation would probably be required to separate out the main hydrocarbon groups:

 

[EJDeBrun]

Thanks everyone for your help!

I should have clarified that this is an ocean planet that mainly uses battery and steam turbine technologies to run itself. They don't use things like petrol. (sorry Brian! OR I would have totally gone the petrol route)

Since it is an ocean planet, I was trying to see if there was a way to make sea derived salt explosive, but it turns out pretty complicated and needs a bunch of specific chemicals that this thread is teaching me would be difficult to differentiate on the fly.

I'm still looking into the Greek fire. Thanks Foxbat!

Having said that, what do ya'll think about sodium-sulfur batteries? They're an industry battery that have high dangers, but let's pretend the planet natives have figured out how to safely handle the raw materials. (See the WIKI here.)

They have close to surface volcanoes that can be a good source for sulfur and obviously sodium could be derived. Sodium burns as a chemical fire when in contact with water. My other consideration was to have bombs made out of glass vials of sodium? Or mixed with a neutral gel substance that can set the water on fire? Thoughts?

Also my human chemist guess the sodium-sulfur combination pretty easily, but I worry if that's believable. Here's my logic for it.

1) Person is a NASA level chemist (like Vogel from The Martian)
2) She is aware of alien technology using electricity as its main source of power.
3) Also aware they do not use petroleum.
4) Conclusion is high capacity industry scale batteries.
5) As of right now, our current battery technology to drive large scale vehicles like cars etc, are limited (See the WIKI here.)
6) This person is aware of excess amounts of sodium and sulfur avail on the planet

Granted, I still put in a note that she will have to test to confirm her guesses regarding the alien battery technology (see the Flame Test here)

So what do ya'll think?

And thanks again for the help!

PS: dannymcg: I see what you did there.

 

[chrispenycate]

Have I missed something? I was attempting to make a mixture that, like Greek fire, sticks to the skin and is not extinguished by immersion in water. To this end it needs to contain its own oxidant - and saltpetre would look like the most conveniently available - on Earth. But on a water planet? The stuff is very soluble in water, so I don't see a convenient way of concentrating it with water universal. Still, there are other oxidants, probably some are lipids. Biological concentration feels like the way to go (saltpetre is extracted mainly from animal dung) and you can develop any species you require.

OK, chemistry wasn't my strongest subject but I did manage to make nitroglycerine (as a potential rocket fuel. Don't.) Ignition should be manageable without too much difficulty - if nothing else, exposing phosphorous.

 

[EJDeBrun]

Have I missed something? I was attempting to make a mixture that, like Greek fire, sticks to the skin and is not extinguished by immersion in water. To this end it needs to contain its own oxidant - and saltpetre would look like the most conveniently available - on Earth. But on a water planet? The stuff is very soluble in water, so I don't see a convenient way of concentrating it with water universal. Still, there are other oxidants, probably some are lipids. Biological concentration feels like the way to go (saltpetre is extracted mainly from animal dung) and you can develop any species you require.

OK, chemistry wasn't my strongest subject but I did manage to make nitroglycerine (as a potential rocket fuel. Don't.) Ignition should be manageable without too much difficulty - if nothing else, exposing phosphorous.

Thanks! That's very useful. I'll look into something like saltpetre, though right now I'm still leaning to the sodium side of a sodium-sulfur battery.

 

[Brian G Turner]

steam

Yes, but ... what's boiling the water to make steam? Normally this is hydrocarbon fuels - ie, coal or oil, but in geological terms both are closely related. Our society has also been heavily dependent on these fuels to provide energy for the manufacturing process itself. If you have metals, how do you smelt them if you don't have fuels to do this with? Btw, Greekfire was also oil-based.

My other consideration was to have bombs made out of glass vials of sodium?

Sodium is extremely reactive with many things - not least air - but it isn't explosive. It's safe enough to demonstrate in high school chemistry classes - even potassium, which is even more reactive. The most reactive in that group is caesium, but I don't think your character is going to find a safe way to handle that!

To be honest, it sounds like you're better off avoiding any kind of specifics and instead be generic, otherwise you're in danger of playing to your weaknesses (ie, chemistry) not your strengths. If your character must use explosives, then it would be better to presume that this society already has some basic forms, and he could simply steal and use these - and to avoid any specific details about what constitutes these explosives in the first place.

For example, I've read a number of thrillers - contemporary, military, and futuristic - but I don't think any of them have ever tried to explain the chemistry of detonators or plastic explosives.

2c.

 

[EJDeBrun]

Yes, but ... what's boiling the water to make steam? Normally this is hydrocarbon fuels - ie, coal or oil, but in geological terms both are closely related. Our society has also been heavily dependent on these fuels to provide energy for the manufacturing process itself. If you have metals, how do you smelt them if you don't have fuels to do this with? Btw, Greekfire was also oil-based.



Sodium is extremely reactive with many things - not least air - but it isn't explosive. It's safe enough to demonstrate in high school chemistry classes - even potassium, which is even more reactive. The most reactive in that group is caesium, but I don't think your character is going to find a safe way to handle that!

To be honest, it sounds like you're better off avoiding any kind of specifics and instead be generic, otherwise you're in danger of playing to your weaknesses (ie, chemistry) not your strengths. If your character must use explosives, then it would be better to presume that this society already has some basic forms, and he could simply steal and use these - and to avoid any specific details about what constitutes these explosives in the first place.

For example, I've read a number of thrillers - contemporary, military, and futuristic - but I don't think any of them have ever tried to explain the chemistry of detonators or plastic explosives.

2c.

Thanks Brian! I think you may have a point about being too specific. Maybe finding the right balance of specifics vs generics is what I need? I'm not sure.

I'm trying to work it out. Sodium-sulfur batteries have been known to cause major explosions in the factories that make them. Also I think about a lot of the exploding electric cars that happen due to overheating or short circuiting batteries. The need isn't like... a huge explosion so much as a form of chemical fire.

As far as the battery technologies, it's all kind of built into the world. They have sub aquatic volcanoes they draw heat form to create the steam. The turbines, in turn, generate the electricity that powers the cities. Batteries are used the primary mobile storage units. You can imagine that this kind of tech could create a "liveable" environment, but would be rift with a lot of complicates and competition. They can still burn things, compressed organic matter etc, but nothing with the explosive power of gasoline/petrol

 

[Ursa major]

and he could simply steal and use these

I can't help feeling that the average reader would probably be much more interested in what is involved in stealing some explosives than what might have to be done to create them.

 

[EJDeBrun]

I can't help feeling that the average reader would probably be much more interested in what is involved in stealing some explosives than what might have to be done to create them.

They don't have explosives, is the thing, so there can be no stealing. My chemist needs to come up with something all on her onesy. Also this is all being decided in a brief conversation. It won't be something long and drawn out (something less than 100 words in dialogue).

FYI: the alien projectiles are all based on electric projection (railguns, coil rifles etc) and not based on gunpowder at all.

Having said that, I think chrispenycate has the best point regarding saltpeter, which should be simple enough for my chemist to make (they can use their own human poop to make it right?) along with the two other powders: sulfur and charcoal to make a basic gunpowder! That should work, right? Helps that sulfur is such a distinguishable element.

Thanks everyone for the help!

 

[Cathbad]

potatoes.

 

[chrispenycate]

I took 'Oceanic planet' to mean the entire surface covered in salt water with no protruding land masses, and any walkable about bits floating vegetation mats or the like. All right - am I not a world builder? That's a challenge, but no more than that. Electricity and salt water are not all that compatible - they go together rather too well, as I learned about forty-five years ago when pioneering underwater housing, and building a traditional chemical battery is extremely complicated in those conditions - but electric rays and eels have developed biobatteries capable of delivering more than a hundred volts while immersed - perhaps biotechnology is a reasonable direction (you could use the delay time while nerves recovered to generate the polyphase signal required for your rail gun, which helps a lot against trying to build generators, or semiconductors)
I don't like sulphur as an electrode/plate. Not because it doesn't have the electrochemical potential with almost any metal, but because it's an almost perfect insulator, and you can't pull the current out though it. Anything done to counter this is going to spoil its voltage generation. Extracting metallic sodium is relatively straightforward - before developing the fluorospar electrolysis process aluminium (then expensive enough to be used in preference to gold on royal crockery) was smelted using pure sodium. You take a sodium salt, quite possibly common sodium chloride, and melt it. (that's quite warm, already) then pass a direct electric current through it. Chlorine bubbles off one plate, the other becomes surrounded by liquid metal - sodium. Freeze out the salt, pour off the metal, don't rinse, and return. But notice, all the energy you're getting out of your batteries has been put in at this stage, so you need your generators of electricity already- tide powered, wind powered, whatever.

As for projectile weapons, have you considered compressed air as motive power? Lighter than most batteries and conveniently available. We used lots of it in the seahouse, sometimes from SCUBA cylinders but there was a buoy tethered above us which used wave power, tide power, storm power to pressurise air and drive it into the depths, where it could be used for a number of things, including running a tiny generator for lighting (Pre LED, so filament or scary fluorescent which, in the perpetually damp conditions tended to bite).

Oops, typical me, info dump info dump. I'll get my wet suit, shall I?

 

[EJDeBrun]

I took 'Oceanic planet' to mean the entire surface covered in salt water with no protruding land masses, and any walkable about bits floating vegetation mats or the like. All right - am I not a world builder? That's a challenge, but no more than that. Electricity and salt water are not all that compatible - they go together rather too well, as I learned about forty-five years ago when pioneering underwater housing, and building a traditional chemical battery is extremely complicated in those conditions - but electric rays and eels have developed biobatteries capable of delivering more than a hundred volts while immersed - perhaps biotechnology is a reasonable direction (you could use the delay time while nerves recovered to generate the polyphase signal required for your rail gun, which helps a lot against trying to build generators, or semiconductors)
I don't like sulphur as an electrode/plate. Not because it doesn't have the electrochemical potential with almost any metal, but because it's an almost perfect insulator, and you can't pull the current out though it. Anything done to counter this is going to spoil its voltage generation. Extracting metallic sodium is relatively straightforward - before developing the fluorospar electrolysis process aluminium (then expensive enough to be used in preference to gold on royal crockery) was smelted using pure sodium. You take a sodium salt, quite possibly common sodium chloride, and melt it. (that's quite warm, already) then pass a direct electric current through it. Chlorine bubbles off one plate, the other becomes surrounded by liquid metal - sodium. Freeze out the salt, pour off the metal, don't rinse, and return. But notice, all the energy you're getting out of your batteries has been put in at this stage, so you need your generators of electricity already- tide powered, wind powered, whatever.

As for projectile weapons, have you considered compressed air as motive power? Lighter than most batteries and conveniently available. We used lots of it in the seahouse, sometimes from SCUBA cylinders but there was a buoy tethered above us which used wave power, tide power, storm power to pressurise air and drive it into the depths, where it could be used for a number of things, including running a tiny generator for lighting (Pre LED, so filament or scary fluorescent which, in the perpetually damp conditions tended to bite).

Oops, typical me, info dump info dump. I'll get my wet suit, shall I?

That is some awesome info! Thank you! I actually think the saltpeter idea is probably more feasible. Marine conditions also has quite a big nitrogen cycle and I could probably have saltpeter already forming over some waste piles of some sort (leaning towards sand filled chamber pots.) Humidity would naturally be high on the planet which would encourage microbial growth that could account for quicker speeds of production.

Compressed air is also a good idea for larger ballistic weapons Probably not as practical for smaller things, but I'll consider it given that there would be a natural limit to rifle use. (something similar to Attack on Titan) Thanks!

And to clarify, the native species don't live underwater. They live on giant city's built like oil platforms over the aquatic volcanoes they draw power from. Those who don't live in city's make their way on floating colonies similar to the villages found in the waters of Vietnam. And like you said, while electricity in marine conditions can be challenging, it's not impossible. Just difficult and not as efficient as other human energy sources.

 

[Montero]

You've got a much bigger worldbuilding credibility problem than your explosive - the platforms. What are they built from? Steel beams? The storms on an aquatic planet will be ferocious without landmass to slow them down. In terms of anchoring a platform over an undersea volcano, you want to do some research on light house building - and see how hard that was and how many were completely washed away by storms.
Compressed air - good idea but you need steel cylinder to contain it.

You need a big industrial base to make steel. Iron ore, coal, generations of expertise, smelters. The thing about technology, or having widely available technology, is having the know how, the materials and the tools. It takes a lot of work to get to the point where an industrial revolution can "take-off".

Finally - why would the dominant species on an aquatic planet need land? (As in platforms) Why aren't they water living?