Sciencemadness Discussion Board

Lab reagent challenge

symboom - 22-11-2019 at 20:54

Using the least amount of otc chemicals how many common reagents could you make
Here is my example

Chemicals
Sodium carbonate
Magnesium sulfate
Sodium chloride

Catalysis
Iron powder
Nickel oxide powder

I would mix the two starting reagents form sodium sulfate add to a electrolysis cell with a separation membrane
I would generate hydrogen from the electrolysis and pass into a chamber that mixes hydrogen and nitrogen to make ammonia then with the oxygen from the electrolysis cell fed into another chamber that mixes oxygen and ammonia gas forming nitric acid.

Adjust the power on the cell and generate sodium hydroxide and sulfuric acid from the sodium sulfate solution.

Add sulfuric acid to the salt and form hydrochloric acid

Chemicals made
Sulfuric acid
Hydrochloric acid
Ammonia
nitric acid



Mesa - 22-11-2019 at 21:14

Should we assume limitless access to equipment, with the only restriction being the starting reagents?

The challenge might get a bit ridiculous, but in a good way!

symboom - 22-11-2019 at 21:20

Yes I should have included limitless access to equipment to the challenge let's see what others come up with

[Edited on 23-11-2019 by symboom]

Mesa - 22-11-2019 at 21:42

Picking up from your H2SO4:

Make nickel sulfate from nickel oxide and sulphuric acid.
Melt iron powder into electrode sized plates/mesh.
Make 2 nickel coated electrodes.
electrolyze a 50% H2SO4 solution to produce H2O2

Chemicals made:
Nickel sulfate
Nickel metal
Iron sulfate(i assume electrodes will degrade fast.)
Hydrogen peroxide


If any NiO is produced during electrolysis it's a non-starter I think... NiO catalyzes H2O2 decomposition from memory.


Edit: Took the liberty of assuming limitless quantities of starting chemicals.

[Edited on 23-11-2019 by Mesa]

[Edited on 23-11-2019 by Mesa]

Vomaturge - 22-11-2019 at 22:44

My initial thoughts? The first example mentioned water and air, but didn't include them in the chemical list. And ammonia/nitric production is notoriously hard to do.

I suppose another way to do the challenge would be using equipment you have successfully improvised from otc sources. So if my stove/blowtorch can't get hot enough to pyrolyse sodium carbonate or melt sodium chloride, or my DIY electrolysis cells are too poorly made to effectively separate and store an acid/base or an alkali metal/halogen, or my iron shavings are worthless for making ammonia, etc... then too bad. I lose. But I'll probably lose as is because I don't have a lot of time right now to try actual reactions at home.
Assuming I could, I could get MgCO3 and Na2SO4 by a simple precipitation reaction. But If I could heat the sodium carbonate to about 1000C and capture the decomposition products, I would get sodium oxide and carbon dioxide. Adding some of the sodium oxide to water would get me sodium hydroxide, adding magnesium sulphate to that would create sodium sulphate as well as magnesium hydroxide. Symboom's electrolysis processes could make sulphuric acid and from there hydrochloric, as well as hydrogen and oxygen. A bit of the hydrochloric acid could be used to form a magnesium chloride solution, since this would be a difficult salt to precipitate directly from magnesium sulphate and sodium chloride. Other electrolytic processes could convert salt and water into (depending on the precise conditions) sodium hydroxide hydrogen and chlorine, sodium hypochlorite and hydrogen, or even sodium chlorate and hydrogen. But again, using only "OTC equipment," not likely. Even more improbable, but not necessarily impossible, would be to use high temperature electrolysis to form elemental sodium and magnesium. Magnesium could likely violently reduce sulphate to sulphide, you know, just because. It could likely be reacted with water or acid.

Assuming it all went according to plan I would take MgSO4, Na2CO3, NaCl, and H2O and get Na2O, CO2, NaOH, Mg(OH)2, MgCO3, Na2SO4, HCl, H2SO4, MgCl, NaClO3, NaOCl, HClO3, ClO2, Cl2, O2, H2, Na, Mg, MgS, H2S, and, with enough equipment and energy, pretty much any stable combination of the atoms involved.
With unlimited equipment? ANY conditions? Then as long as the final products are made of matter that originally came from the precursors, we're okay.

I'll start with hydrogen. Lots of it. Make it into stars of assorted sizes, wait a few billion years and have enough elements and compounds to make EVERY other compound.

j_sum1 - 23-11-2019 at 00:51

Quote: Originally posted by Vomaturge  

I'll start with hydrogen. Lots of it. Make it into stars of assorted sizes, wait a few billion years and have enough elements and compounds to make EVERY other compound.


I think that is cheating. You can't on the one hand complain that you don't have enough time and on the other hand invoke stellar mechanisms. It is just not fair to those of us who fon't have a spare star and a couple of billion years to invest OKn the project.

Mesa - 23-11-2019 at 05:14

It's really taking my previous comment to it's logical conclusion.

Irrational sure, but who ever let rationality get in the way of a good plan?

Vomaturge - 23-11-2019 at 05:48

Quote: Originally posted by j_sum1  
Quote: Originally posted by Vomaturge  

I'll start with hydrogen. Lots of it. Make it into stars of assorted sizes, wait a few billion years and have enough elements and compounds to make EVERY other compound.


I think that is cheating. You can't on the one hand complain that you don't have enough time and on the other hand invoke stellar mechanisms. It is just not fair to those of us who don't have a spare star and a couple of billion years to invest OKn the project.

That's why I split my submission into three possible scenarios. The first is what I would likely be capable of making in my own lab, with current time and "OTC equipment." All I do is swap ions to precipitate two new compounds.

Next up, I have a series of reactions, which at different points produce at least 20 separate compounds.This outcome is similar to the OP's, in that it's possible but not plausible to do at home. I could maybe even argue that this set of reactions would be more likely to work with in a home lab than the OP's, but it's a moot point. Many of these reactions would be difficult to impossible without specialized equipment and a lot of time/money; it is unlikely that I would succeed in making all of them work. So at this point, I am assuming I can have any time/equipment needed, regardless of whether I really do.

I was originally going to save the final answer as a cheeky reply when Symboom OK'd the use of ANY equipment. But I thought it would fit well as a progression from my last "impossible" project. Again, I am doing something which I would be incapable of in real life.

fusso - 23-11-2019 at 07:18

I remember there's a similar challenge in whimsy previously?

clearly_not_atara - 23-11-2019 at 10:49

Um, ok. Let's go with urea -- I have to choose some kind of nitrogen source, and as long as we're assuming "limitless" amounts, urea is the most OTC. And table salt, and limestone, and wood. I'm gonna use a lot of wood. But it's just wood.

Anyway, the obvious:

CaCO3 + Δ >> CaO (s) + CO2 (g) (potentially usable CO2)

wood + O2 + Δ >> ash + CO2 (g) (probably not usable CO2)

ash + H2O >> K2CO3 (aq) + carbon

K2CO3 (aq) + CaO (aq) >> KOH (aq) + CaCO3 (s)

The unobvious:

wood + grinding >> sawdust

KOH (aq) + sawdust >> K2C2O4 (aq) + delignified sawdust

2 K2C2O4 (aq, conc) + 2 CO2 (g, high pressure) + 2 H2O (l) >> KHCO3 (aq) + KH3(C2O4)2 (s) (potassium tetraoxalate, solubility 2.5% w/v)

The cliche:

(NH2)2CO + KOH/NaOH >> K2CO3/Na2CO3 + NH3 (g)

NaCl (aq, conc) + NH3 (g) + CO2 (g) >> NaHCO3 (s) + NH4Cl (aq)

NH4Cl (aq) + CaO (aq) >> CaCl2 (aq) + NH3 (g)

The symphony:

2CaCl2 (aq) + KH3(C2O4)2 >> 2 CaC2O4 (s) + KCl (aq) + 3 HCl (aq)

Na2CO3 + Δ (1400 C) >> Na2O + CO2 (g)
(cf https://www.solvay.us/en/binaries/HeatEffects_of_the_TronaSy... )

Na2O + O2 (g) + pressure/agitation (150 C) >> Na2O2

Na2O2 (aq) + KH3(C2O4)2 (aq) >> H2O2 (aq) + Na2C2O4 (aq) + KHC2O4 (aq) + distillation >> H2O2 (aq)
(with slow oxalate-peroxide rxn rate at near-neutral pH https://www.osti.gov/servlets/purl/6229619 )

sawdust + HCl (aq, conc) + distillation >> levulinic acid

levulinic acid + NaOH + Δ >> butanone

sawdust + HCl (aq, dilute) + (240 C, high pressure) >> (dissolved lignin) + cooling >> precipitated lignin

precipitated lignin + H2O2 + NaOH >> NaHCO2
(preparation and oxidation of precipitated lignin: https://link.springer.com/content/pdf/10.1385/ABAB:84-86:1-9...)

NaHCO2 + HCl >> HCO2H (distilled)

HCO2H + H2O2 + butanone >> ethyl acetate

ethyl acetate + NH3 (aq) (24-72h) >> acetamide + ethanol

acetamide + carbon + (reflux) >> acetonitrile

Obviously I've pushed the "limitless" equipment pretty far with the calcining of sodium carbonate and Na2O2 production, and the yields of organic materials and potassium compounds from wood are all on the order of 10%, but you do get somewhere after a while, at least in a formal sense! If you replace CaCO3 with BaCO3, the peroxide part gets a lot easier and everything else remains roughly identical.

j_sum1 - 23-11-2019 at 18:41

So... clarify for me. Is this a challenge for us to come up with a concept or is it a competition for us to undertake practically?

fusso - 23-11-2019 at 19:27

I'd like to see it being undertaken.

woelen - 24-11-2019 at 23:48

What practically can be done at reasonable cost from OTC chemicals (NaCl and KCl) is making NaClO3 and KClO3. I did this and have written about this on my website. Other members have done also. I only made a small amount, appr. 250 grams over all experiments I did with this, some members over here made larger quantities, used in pyrotechnics.

Even the (di)chromate , needed for acceptable efficiency can be made from OTC chemicals:
- Dissolve some chromium metal in HCl.
- neutralize with NaOH or NaHCO3
- add a little bleach, until the liquid just turns lemon-yellow
- add HCl dropwise until the liquid turns yellow/orange (only very little HCl is needed for this)
- mix this yellow solution with your electrolyte, no need to first isolate any chromate