Sciencemadness Discussion Board - Everyday Chemistry - Powered by XMB 1.9.11 (Debug Mode)

restarting this thread; hopefully it will be merged when the One, True Thread reappears.

.

So what happened to the original thread mods, anybody ?

roXefeller - 28-6-2018 at 17:45

Got a bunch of scrap iron sitting in a bucket of muriatic acid, on its way to Fe2O3

I need to get some of that going. Looking for a handy way to light a tenaciously wet barrel fire, in style. Got the aluminum, but I don't think I ever bought iron oxide.

JJay - 29-6-2018 at 23:00

I cleaned and organized glassware. I also organized some of the chemicals.

JJay - 5-7-2018 at 13:50

I started a stripping run of a gallon of Klean Strip Premium. I ended up going through an entire sack of ice so I stopped after about two liters. The can still smells like DCM, so I'll try to finish it ths weekend.

DraconicAcid - 5-7-2018 at 20:01

Tested different versions of the piperine extraction from black pepper lab.

symboom - 5-7-2018 at 20:54

Tested bromine in silica to see if it will absorb

Studied about internal oxidtion on such as light sensitive potassium ferrioxalate and ammonium permanganate

[Edited on 6-7-2018 by symboom]

[Edited on 6-7-2018 by symboom]

TheMrbunGee - 6-7-2018 at 10:47

I started a stripping run of a gallon of Klean Strip Premium. I ended up going through an entire sack of ice so I stopped after about two liters. The can still smells like DCM, so I'll try to finish it ths weekend.

I had success distilling DCM just with cold tap water, 30 cm Liebig condenser @ 400ml/h

JJay - 6-7-2018 at 11:30

I had success distilling DCM just with cold tap water, 30 cm Liebig condenser @ 400ml/h

I did it with that exact setup when I was first starting out, but I don't think it's as efficient as using ice water with a 30 cm Dimroth, and I had horrible nosebleeds the next day after trying it with a Liebig. Also, I didn't have a convenient tap the other day.

TheMrbunGee - 7-7-2018 at 00:36

I had success distilling DCM just with cold tap water, 30 cm Liebig condenser @ 400ml/h

It could be faster, but I had a closed system (not counting vacuum nozzle, and no vapor came out of it.

Plunkett - 13-7-2018 at 12:30

A few weeks ago I went rockhounding at an old zinc mine and picked up some glossy black rocks which I thought were sphalerite, hoping to isolate zinc from them. Yesterday, I began to crush the rocks up with a hammer and the powder was red which I thought was strange, but I do not know a lot about minerals so I figured it was nothing and kept going. It was not until I noticed rock fragments sticking to a nearby magnet that I realized the mineral was hematite, not sphalerite. A little disappointed, I cleaned up the hematite and instead made a small dot of copper metal by the carbothermal reduction of basic copper carbonate recovered from the inside of some old copper pipes. I have some malachite and azurite fragments from the same mine and once I get my technique down I want to try and smelt them.

[Edited on 13-7-2018 by Plunkett]

AlexC - 13-7-2018 at 12:50

Rock is always useful. I mean you are not searching for anything in rock. Whole rock is something. All elements we need. Like H, He, Li, Be, B, C, N, O, F, N, O, F, Ne...whole periodic table. That's what changed my perception about life. I noticed everything is elements. It would be stupid to just try to extract one element and throw processed rock away. When doing something, do it completely. Do not steal minerals from Mother Nature, she will punish you.

Or this whole post in one sentence: TAKE IT OR LEAVE IT.

[Edited on 13-7-2018 by AlexC]

DraconicAcid - 13-7-2018 at 14:21

I tried to convince my dean to look for funding for a benchtop NMR spectrometer.

j_sum1 - 13-7-2018 at 17:55

Back in the lab after a bit of absence. Preoccupied with -- well, life stuff.

Huge pile of dirty stuff to clean up from last time all of which had accumulated a decent layer of dust.
I managed to break a beaker and the stem of a take-off adapter. My most common cause of breakages is me cleaning stuff.
I installed a screen in the lab (spare TV) and attached it via HDMI socket to the computer in the office next door. Already it is more useful than I imagined it would be. So nice to be able to look up stuff while working in the lab.

I am half-way through purifying some dioxane I made last night. I managed to get the tarry mess at the end of the synth to boil over and flood the condenser. Twice. But now it is fractionally distilling nicely and it looks like I will have a good product.

JJay - 4-8-2018 at 17:29

I put 100 grams of technical barium carbonate into a 5L beaker and added 1000 mL of 5% cleaning vinegar. Phew! It stinks! After it finishes reacting, I am going to filter, add sodium hydroxide, evaporate off some of the water at low heat, chill, then recrystallize the precipitate and dry it in my desiccator. I'm going to have to read up on suitable desiccants... removing the last water of hydration is very hard, but I'd like to get the product as dry as practical.

Loptr - 4-8-2018 at 18:04

I want to ask you guys how do you have time for such a number of experiments in conjunction with life? I have a wife and two kids. They demand most of the time I have outside of work.

How do you guys do it? I used to have a lot of time to myself for stuff like this. It's really got me down lately.

j_sum1 - 4-8-2018 at 18:12

Hang in there, Lotptr. I am in the same position. Basically, I am finding that I need to schedule in some lab time in a chunk and go hard when I get the chance. And accept the fact that it doesn't happen as regularly as I would like.

I got into the lab the other night for a continuation of dioxane synthesis and found that it had been three weeks since my last visit. Distillation took longer than I anticipated and I ended up going to bed at 2:00 am

I can see that in a couple of months work things might be a bit more settled and I might be able to do more. But then again, it is probable that other priorities will sneak in and it will be just as difficult. Ultimately I have to recognise that a bit of me-in-the-lab time is important enough for me to have to schedule it. And I have to accept that much of the time I will have to get my fix by dropping in here and reading.

Loptr - 4-8-2018 at 18:33

Quote: Originally posted by j_sum1

Hang in there, Lotptr. I am in the same position. Basically, I am finding that I need to schedule in some lab time in a chunk and go hard when I get the chance. And accept the fact that it doesn't happen as regularly as I would like.

I got into the lab the other night for a continuation of dioxane synthesis and found that it had been three weeks since my last visit. Distillation took longer than I anticipated and I ended up going to bed at 2:00 am

I can see that in a couple of months work things might be a bit more settled and I might be able to do more. But then again, it is probable that other priorities will sneak in and it will be just as difficult. Ultimately I have to recognise that a bit of me-in-the-lab time is important enough for me to have to schedule it. And I have to accept that much of the time I will have to get my fix by dropping in here and reading.

See that is me right there! Thanks for that j_sum1. I appreciate the advice.

JJay - 5-8-2018 at 00:02

I usually try to run multiple low-maintenance experiments simultaneously while I do other things. I'm planning on using the barium hydroxide to purify the product from a couple of experimental glyoxylic acid synths, but I'll also put some in a bottle so that I have some ready to go next time I want some (it's pretty useful).

Technical grade barium carbonate is almost as cheap as dirt, but it is very impure. I think it's possible to prepare rather pure barium compounds from it, though, if the right steps are taken.

happyfooddance - 5-8-2018 at 10:47

I just finished purifying some phenolphthalein that I made about a week ago. I used phthalic anhydride that I prepared from phthalic acid from hydrolysis of phthalate esters extracted from scrap vinyl, and phenol that I prepared from aspirin from the dollar store. A lot of work but rewarding.

Now I have to prepare some standardized solutions (sodium carbonate, HCl, NaOH, ethanolic KOH)... It is hot in the lab though, so keeping everything 20°C is a chore that I am not looking forward to. Does anybody else feel like any time one task is completed, another 10 get added to the to-do list?

JJay - 5-8-2018 at 22:25

Here's the barium acetate solution that was left behind after gravity filtering. It has a slight sulfurous odor, and it is obviously impure. I'm not exactly sure what the brown color is... I believe that iron (iii) acetate is rather insoluble. There were iron filings in the barium carbonate; they stuck to the stirbar.

My plan is to add some sodium hydroxide solution, which should precipitate barium hydroxide octahydrate. Heating to boiling and doing a hot filtration will hopefully get rid of any carbonates. I'll probably recrystallize the product a few times for purity then dry it to the monohydrate in a warm oven (easier than using a desiccator).

I have some disgusting and toxic barium waste sludge that I have to dispose of. I'm pretty sure I should not put it down the drain. Right now it is just sitting in a container while I figure out what to do with it.

Heptylene - 8-8-2018 at 04:37

Today I prepared ethyl benzoate from benzoic acid, dry ethanol and sulfuric acid on 0.5 molar scale. For some reason the reaction boiled out of control, flooded the condenser and made a wintergreen-smelling volcano inside my lab. Of course this happened when I left the reaction unmonitored for a few minutes. Only a small portion of the reaction mixture was lost though, and I ended up with 58 % of ester of density 1.04 g/ml, which is fine considering the starting materials are cheap.

This will be used to make triphenylmethanol by reaction with phenylmagnesium bromide.

JJay - 9-8-2018 at 02:45

I made some nitric acid from hardware store chemicals. I haven't titrated it yet, but I'm guessing it is about 50% concentration.

When doing the distillation, I ran a PVC hose from the takeoff outside, and it's a good thing I did - when the potassium bisulfate started to crystallize, it almost all crystallized at once, giving off a lot of heat and overwhelming the condenser, sending boiling hot nitric acid vapors through the hose. I'd never done a nitric acid distillation on this scale before, but I suspected that might happen, so I was prepared.

I didn't get a chance to finish my barium hydroxide because the nitric acid distillation took too much of my attention, but hopefully, I'll get to that tomorrow.

Heptylene - 9-8-2018 at 03:10

Does anyone know what happened to the old thread? I found a link to it but apparently it "doens't exist".

Anyway, today I made some 2,3-dimethoxybenzaldehyde from ortho-vanillin and methyl iodide, with potassium carbonate in acetone. Then I condensed the product with 2-cyanoacetamide to give 2-(2,3-dimethoxybenzylidene)-2-cyanoacetamide as nice white needles.

Interestingly the product has strong blue fluorescence under long wave UV light. With the 3,4-dimethoxy pattern, the fluorescence in turqoise instead. And with the 4-dimethylamino pattern, the fluorescence in bright orange. I'll probably make a thread at some point with more details.

scheme.bmp - 241kB

CouchHatter - 9-8-2018 at 21:24

About 2 months ago somebody had a topic about disappearing threads and falling post counts... Shortly after that the Everyday Science thread disappeared, along with a handful or more other threads. It was probably missed quickly because of its sticky status.

In the OP, no one seemed to know what was going on, but it wasn't exactly the mod lounge. I remember JJay or jsum_1, streety or symboom, aga, maybe coppercone were all there. I can't find it anymore, maybe deleted because I found a duplicate thread from 2015. Pretty sure its simply something to deal with until the forum software is upgraded.

I'm moving into a new lab space! so I'm not exactly working every day on chemistry. Or any day for now.

JJay - 10-8-2018 at 01:16

I don't know what happened to it, and I'm not going to speculate. I had probably at least 50-100 posts on that thread.

I did not do any chemistry today because my Internet was down for much of the day, and I didn't have the necessary references. But I will be back at it in full force tomorrow.

arkoma - 10-8-2018 at 11:55

Quote: Originally posted by j_sum1

I am half-way through purifying some dioxane I made last night. I managed to get the tarry mess at the end of the synth to boil over and flood the condenser. Twice.

That is some tarry ass stuff too, but amazingly comes out of the glass easy. Finally bought a small (100ml) boiling flask for the pursuit of my esters.

Medical hassles keep me out of the lab, kids are grown! (In hospital right now, just had surgery. Again *sigh*)

JJay - 19-8-2018 at 21:14

I made a nice little batch of chloroform with the last of my bleaching powder in three runs. I don't recommend doing this unless you have a surplus of bleaching powder, but you can add 100 mL of acetone to 300 grams of standard pool grade calcium hypochlorite and 1.5L water in a 3L flask in an ice bath with mechanical stirring with a reflux condenser (add acetone slowly or the mixture might boil and foam excessively, filling the condenser with suds. if that happens, dump ice water through the condenser to avoid making a big mess). Once the reaction stops, you can distill off the chloroform on a water bath. It is possible to do the reaction without mechanical stirring by shaking the flask and cooling it repeatedly until shaking doesn't make it warm up, but that is an enormous pain.

The crude product (which is what I have here) will be wet and probably contaminated with acetone. I'm going to wash mine with concentrated sodium bisulfite solution, dry it over potassium carbonate, distill it, stabilize it with 1% ethanol, and store it with the rest of the lab chloroform.

Now that I've used up the last of my calcium hypochlorite, I think I'm going to stick with making chloroform with chilled liquid bleach. It's much less work that way.

[Edited on 20-8-2018 by JJay]

JJay - 30-8-2018 at 00:36

Earlier I set up a hot filtration apparatus and did a dry run (I've never actually done a hot filtration before). Right now I'm boiling down some crude barium hydroxide solution. It likely contains a little less than a mole of barium hydroxide, so I'm going to try to get the volume down to about 200 mL then filter and refrigerate. I'm hoping for white crystals. I have a bucket filled with dilute sulfuric acid that contains the waste and the paper towels used to do the cleanup.

Oh and I'm also running a fractional distillation and slowly evaporating a solution on a steam bath.

[Edited on 31-8-2018 by JJay]

Heptylene - 31-8-2018 at 02:46

I made 400 grams of 60 % nitric acid by distillation from sodium nitrate and sulfuric acid. I tried to increase the strength of the acid to reach around 65-70 %, but this seems impossible without a fractionating column.
The product will probably be used to make some o- and p-nitrotoluene.

I'm also purifying cinnamaldehyde from cinnamon bark oil using sodium metabisulfite. The goal is to form the bisulfite adduct, remove the rest of the organics by filtration and the deprotect the cinnamaldehyde using a base. I wish I had an overhead stirrer because the bisulfite adduct forms a thick slurry that is difficult to stir.

I'll post a thread when I'm done.

JJay - 31-8-2018 at 19:21

I did a hot filtration of crude barium hydroxide solution and then washed the filter cake and beaker with about 100 mL of boiling water. Unfortunately, a small amount of silty material (likely barium carbonate) made it through the filter paper and cotton ball. Right now the solution is cooling. I'm hoping that the silty material will go through the filter paper just as easily when I filter off the barium hydroxide, but I imagine I'll have to recrystallize.

mayko - 18-9-2018 at 18:15

Turned some manganese sulfate into manganese carbonate

JJay - 19-9-2018 at 05:39

Getting ready to run some distillations....

mayko - 20-9-2018 at 19:02

Turned some manganese sulfate into manganese carbonate

I made a slurry in water and added HCl and it's a chloride now.

one cool thing is that after additions of HCl, when the effervescence died down, there was a clear stratification of the translucent acidified layer and the murky lower layer still containing suspended carbonate. There seemed to be points of reaction between the two, visible as a spot of bubbling on the dark surface. They seemed to have some interesting dynamics: some of these upwelling spots persisted for a while, some extinguished quickly, and some grew into a large foaming for a moment

mayko - 23-9-2018 at 15:42

I've been converting oxalic acid to formic acid all weekend. It's a cute little reaction cycle catalyzed by glycerine, in which a glyceryl oxalate ester is formed, the ester is decarboxylated to a glyceryl formate ester, and the ester is hydrolyzed and the formic acid distilled off. Several literature sources call for thorough drying of the glycerine beforehand, but it's not obvious why, and NurdRage didn't make any special mention:

https://erowid.org/archive/rhodium/chemistry/formic.acid.htm...
https://www.youtube.com/watch?v=ceL-I0azPH8 (with a guest appearance from Gary the Bug)

Anyway, I'm coming up on ~100 mL of distinctly anty-smelling crude product

JJay - 23-9-2018 at 15:53

I've been thinking about doing that too. I have to wonder if there isn't an easier way, though... something like hydrogen peroxide and methanol....

Oh and I've been purifying solvents all weekend. I finally managed to clean my sep funnel by putting some abrasive cleaner and a handful of coins into it and swirling it around. There was a waxy coating clinging to the walls, and now the funnel has that sparkling new glassware look to it.

[Edited on 23-9-2018 by JJay]

ninhydric1 - 23-9-2018 at 20:21

Currently dissolving a neodymium magnet in sulfuric acid. Also made a few mL of crude methyl salicylate. Also mixed 50 mL of a lacquer thinner with 50 mL of water to determine the toluene/DCM concentration. Will start separating the components of the thinner next week when I have time, as toluene is unfortunately not sold as a pure product anymore where I live.

DavidJR - 24-9-2018 at 12:42

Oh and I've been purifying solvents all weekend.

That's what i'm doing now - I had 20L of various waste solvents, most of which mixtures of methanol/water eluent waste from my HPLC.

weilawei - 24-9-2018 at 17:39

Screwed up and made a pretty hefty amount of bismuth oxynitrate. Went and hydrolyzed my bismuth (III) nitrate I'd made by dissolving metallic bismuth in nitric acid.

Damn. Would dissolving it in concentrated HNO3 push the equilibrium back the other way and allow me to recover the nitrate?

Edit: I believe my new strategy could be to dissolve it in weak nitric acid solution, and neutralize with sodium carbonate to get bismuth (iii) oxide, followed by digestion in HCl and reduction with aluminum to yield metallic powdered bismuth, filtered, added to conc. nitric acid, and evaporated. Phew! That's one heck of a round-trip if I can't just add it back to conc. nitric acid....

[Edited on 25-9-2018 by weilawei]

Daffodile - 25-9-2018 at 08:40

Anyone on here ever thought about making some Xylyl Bromide? Found some Sodium Bromide solution at the store the other day, when I ran Chlorine through it I got some nice dark droplets of Bromine. I destroyed that sample obviously but am considering making some Xylyl Bromide by just mixing Xylene/ Bromine in reflux and irradiating (patent says a lamp should be sufficient).

I know that there will be a couple brain cells lost in the experiment but it seems like a pretty interesting chemical overall. I've made and tested a couple other similar chemicals before and had a lot of fun, like chloropicrin or iodoacetone.

JJay - 29-9-2018 at 17:29

I removed a couple of centimeters from my 20 cm thermometer tube so that it will fit into a 3 L flask. I am not very experienced at glassblowing, but I managed to get the end to seal without doing too bad of a hack job.

I also constructed a large gravity filtration apparatus by drilling numerous small holes into the bottom of a 3.75 L ice cream bucket. The bottom of the pail is exactly the same size as a coffee filter. It works pretty well except the bucket is a little too flexible to hang without the sides caving in and reducing capacity. I'm going to try it with a more rigid pail.

ninhydric1 - 30-9-2018 at 12:36

Just distilled out DCM and toluene out of a refinisher. Will do a fractional distillation when I have time to separatye the two.

Sulaiman - 1-10-2018 at 00:11

I also constructed a large gravity filtration apparatus by drilling numerous small holes into the bottom of a 3.75 L ice cream bucket. The bottom of the pail is exactly the same size as a coffee filter. It works pretty well except the bucket is a little too flexible to hang without the sides caving in and reducing capacity. I'm going to try it with a more rigid pail.

For my diy heating mantle I bought some glass fibre cloth
https://www.ebay.co.uk/itm/0-03mm-Ultra-Thin-Fiber-Glass-Fab...
It is very fine mesh, it has unbroken threads / no loose bits, it is surprisingly strong, and resistant to heat, acids etc.
I think that it may make an excellent filter material,
with or without mechanical support.

It also looks suitable as a simple mechanical membrane for an electrochemical cell.

JJay - 1-10-2018 at 00:15

It worked OK, but it still takes forever to filter calcium salts.

I was thinking about doing that with some ceramic paper, but it's a little on the expensive side to use for filters... interesting idea, though.

JJay - 1-10-2018 at 09:24

I put some more solvents in bottles. I probably ought to recycle my waste toluene.... At some point today, I plan to recrystallize some sodium carbonate.

Texium - 1-10-2018 at 11:44

Quote: Originally posted by Daffodile

Anyone on here ever thought about making some Xylyl Bromide? Found some Sodium Bromide solution at the store the other day, when I ran Chlorine through it I got some nice dark droplets of Bromine. I destroyed that sample obviously but am considering making some Xylyl Bromide by just mixing Xylene/ Bromine in reflux and irradiating (patent says a lamp should be sufficient).

I know that there will be a couple brain cells lost in the experiment but it seems like a pretty interesting chemical overall. I've made and tested a couple other similar chemicals before and had a lot of fun, like chloropicrin or iodoacetone.

Doesn't seem worth it to me since you'll be using mixed xylene isomers. You'll also get varying levels of substitution so you'll end up with a whole witch's brew of partially brominated xylene isomers...

mayko - 3-10-2018 at 17:26

Doing my first fractional distillation (of the crude formic acid). Water coming over right now ~101C!

Eddygp - 5-10-2018 at 15:57

Cracking some dicyclopentadiene from a very old bottle... it decided to stop halfway through so who knows what kind of contaminants/degradation products there are in that starting material (yield~35% maybe?). Hours fighting with the equipment to heat up sufficiently and then that letdown, kind of a bad day in labs today.

JJay - 6-10-2018 at 20:05

I started building a new fume hood. Also, I dried some molecular sieves.

weilawei - 11-10-2018 at 20:25

Quick and dirty neutralization of NaOH with acetic acid to produce sodium acetate. This will be dried to the anhydrous form in an oven at 149°C for 2 hours with stirring at 30 minute intervals (works beautifully, without decomposition), then recrystallized from a supersaturated solution with a seed crystal (highly entertaining to watch!).

I have pictures of the last time I recrystallized sdium acetate, though the solution was brown from decomposition products (while I was still nailing down the procedure). I burnt it the first time. It wasn't pretty, and scraping your product off the bench is no fun. That's after dissolving a brick of charcoal acetate

and cleaning it up with activated charcoal and repeated filtration.

Note the condensation on the beaker rim. The solution was initially cooled to room temperature very slowly, and that condensation is entirely from the water vapor driven off by the exothermic crystallization of the sodium acetate which started only seconds before the photo and almost instantly crystallized the entire solution. The second photo is after filtering, washing, and drying on the pump.

CH₃COONa•3H₂O

[Edited on 12-10-2018 by weilawei]

nimgoldman - 12-10-2018 at 12:02

My first alkyl halide - bromoethane, fractionally distilled between 38.4-38.7 °C

mayko - 25-10-2018 at 21:02

got some nice copper formate crystals cropping up, clusters of flakes though I want to reheat & concentrate the solution some more.

Jackson - 26-10-2018 at 08:44

Just did some tests on a sample that I made of what I though to be sodium tungstate only to find out that my tungsten I used is probably zinc and my sample is Zinc Sulfate.

fusso - 26-10-2018 at 09:37

Quote: Originally posted by Jackson

Just did some tests on a sample that I made of what I though to be sodium tungstate only to find out that my tungsten I used is probably zinc and my sample is Zinc Sulfate.

Obviously you should have researched a bit to know that H2SO4 isn't needed to dissolve W.

Jackson - 26-10-2018 at 10:13

Quote: Originally posted by fusso

Quote: Originally posted by Jackson

Just did some tests on a sample that I made of what I though to be sodium tungstate only to find out that my tungsten I used is probably zinc and my sample is Zinc Sulfate.

Obviously you should have researched a bit to know that H2SO4 isn't needed to dissolve W.

I used Sulfuric and H2O2 to speed it up. I understood that sulfuric is not needed but I assumed turning it into Caro’s Acid could act as a better oxidizer than just H2O2

JJay - 26-10-2018 at 20:55

I made some nitric acid out of a sulfuric acid solution that had been sitting around for almost a month waiting to be made into nitric acid. I also did a third recrystallization of some sodium carbonate, which is currently drying in an oven. Hopefully sometime next week I'll get to titrate my stocks of nitric acid. I also want to make some glacial acetic acid and see if I can get it to 99.9%+, and I plan to research chrome plating and finish my fume hood.

nimgoldman - 27-10-2018 at 03:19

Just synthesized tetrahydroharmine (leptaflorine) from harmaline via reduction in zinc-acetic acid.

The tetrahydroharmine (two larger beakers) glows with faint blue color compared to harmine that glows green in UV. This confirms the transformation has taken place.

Next time I will do the synthesis without allowing oxygen to form side products.

Ubya - 27-10-2018 at 12:25

today is lab day!!! (after a week of running to and from university)

this morning i put together and tested my chinese H01-2 oxy-acetylene torch using a disposable oxygen bottle and butane (from a dismantled blowtorch), melted an iron nail and some refrigeration copper tubing withoutany problems, i should use the proper gas tubing and flash arrestors, maybe next time

then i added to my diy fumehood water lines for my distillations (still need to work on the cooling system)
and last i evaporated some purified ZnSO4 solution i made 2 years ago from H2SO4 and zinc from batteries and left sitting on the bench for all this time, i wanted to make doped ZnS glow in the dark powder (and maybe doping it with Ag to make it fluoresce when hit by alfa or beta radiation)

JJay - 4-11-2018 at 15:53

Today I calibrated my thermometers and found that my mercury thermometer is accurate at around freezing but several degrees off at the boiling point of water. My alcohol thermometer is several degrees off at around freezing but accurate at the boiling point of water (last time I checked, it was accurate at freezing and read several degrees too high at the boiling point of water). I guess I should check my thermocouples....

Edit: my PID controller is dead on at 0.0 C and also dead on at 99.9 C. Cool.

[Edited on 5-11-2018 by JJay]

Sulaiman - 5-11-2018 at 03:07

Today I calibrated my thermometers and found that my mercury thermometer is accurate at around freezing but several degrees off at the boiling point of water. My alcohol thermometer is several degrees off at around freezing but accurate at the boiling point of water (last time I checked, it was accurate at freezing and read several degrees too high at the boiling point of water). I guess I should check my thermocouples....

Edit: my PID controller is dead on at 0.0 C and also dead on at 99.9 C. Cool.

[Edited on 5-11-2018 by JJay]

did you use distilled water for the melting ice and boiling water references ?
and compensate for your local atmospheric pressure ?

I ask because I've not encountered a thermometer that is accurate at 0^oC but not at 100^oC,
and in a U2U I recently told a newer member that this is highly unlikely,
so I'd like to clear this issue in my mind.

Has anyone else found an unbroken liquid filled thermometer that is in calibration at 0^oC but not at 100^oC ?

[Edited on 5-11-2018 by Sulaiman]

JJay - 5-11-2018 at 08:11

I knew for a fact that the alcohol thermometer was low quality and gave inaccurate temperature readings, but it was something like $1.20 with free shipping. The mercury thermometer came from a reputable supplier and was expensive, but it had given what I felt was an anomalously low reading last time I used it.

I compensated for local atmospheric pressure (otherwise 99.9 C would not be "dead on"). I did not use distilled water, but the water had a low mineral content, so the melting point depression and boiling point elevation would be insignificant. Also, in this case, one thermometer is accurate at around 0 C and the other is accurate at around 100 C, yet they both read too low at the other extremes; dissolved minerals can't cause that scenario.

Any calibration procedure for a thermometer will tell you to take multiple readings. They don't all say to use distilled water. (For example: https://www.epicurious.com/expert-advice/how-to-calibrate-a-...) In some places, calibration wtih distilled water would be necessary.

Taking only one temperature reading for calibration is bad practice.

Chloroform Production Optimization, part 1

JJay - 12-11-2018 at 06:39

4 gallon jugs containing 3785 mL of 6% store brand bleach were purchased and chilled to 5 C. For each jug of bleach, the following procedure was performed:

1. Remove 85 mL of bleach from the jug.
2. Add a measured quantity of solvent-grade acetone.
3. Tightly cap and shake, then loosen the cap and chill in refrigerator for 2 h.

Each jug was capped and shaken one additional time, after which the cap was loosened and the mixture was allowed to chill for 6 h. The organic and aqueous layers were separated, and the following yields of crude chloroform were obtained from the corresponding quantities of acetone:

A. 80.9 mL acetone => 54 mL chloroform (10% excess of acetone)
B. 73.5 mL acetone => 53 mL chloroform (stoichiometric quantities)
C. 66.2 mL acetone => 49 mL chloroform (10% excess of hypochlorite)
D. 58.8 mL acetone => 43 mL chloroform (20% excess of hypochlorite)

It appears that there is no advantage to using an excess of hypochlorite. The advantage of using an excess of acetone is not really evident from this experiment since the purity of the products is not known.

[Edited on 12-11-2018 by JJay]

Sulaiman - 12-11-2018 at 07:01

As I am unlikely to achieve exact stoichiometry in most similar experiments
so I usually decide in advance which reactant will be in (slight) excess,
often it is just the cheapest reactant,
sometimes it is to make separation of product easier.
so
in this case I would use a slight excess of bleach to ensure that all of the acetone is used.
- because I probably would not initially bother with an accurate titration of the bleach

JJay - 12-11-2018 at 07:25

My purification procedure removes excess acetone. I'm planning on making a liter or so of chloroform, so I'd like to have an optimized process.

Sulaiman - 12-11-2018 at 09:13

I made chloroform using a cheap dilute domestic bleach which gave a little product,
as chloroform is about 1% miscible in water I wanted to reduce the starting water content,
so I thought " why not use my 15% sodium hypochlorite solution ? "
... quite energetic

So too dilute needs distillation to recover all of the chloroform
and too concentrated needs unobtainable cooling.
that's all I know.

DavidJR - 12-11-2018 at 09:34

I made chloroform using a cheap dilute domestic bleach which gave a little product,
as chloroform is about 1% miscible in water I wanted to reduce the starting water content,
so I thought " why not use my 15% sodium hypochlorite solution ? "
... quite energetic

So too dilute needs distillation to recover all of the chloroform
and too concentrated needs unobtainable cooling.
that's all I know.

I tried using the dirt cheap tesco bleach (3% NaOCl if I recall correctly) and didn't get a high enough product concentration for it to separate out at all.

Even using 14% there's still a lot of water to get rid of for fairly little product.

However I have no motivation to make any more since I've ordered 1L for far less than it would cost me to make.

morganbw - 12-11-2018 at 11:05

Quote: Originally posted by DavidJR

So too dilute needs distillation to recover all of the chloroform
and too concentrated needs unobtainable cooling.
that's all I know.

Some wisdom there. There really seems a balance is required and this is not chloroform specific.

[Edited on 11/12/2018 by morganbw]

JJay - 13-11-2018 at 19:48

So too dilute needs distillation to recover all of the chloroform
and too concentrated needs unobtainable cooling.
that's all I know.

The usual trick for conducting highly exothermic reactions in a controlled manner is to avoid mixing all of the reactants together at once. In this case, you could add the acetone in small portions with cooling in between.

Ubya - 17-11-2018 at 03:49

hoping to get a few ml of limonene from 530g of orange peels

Sulaiman - 17-11-2018 at 04:51

If successful to any degree, or even if you realise why it was not,
then please report with some notes as this and similar are on my list.

Ubya - 18-11-2018 at 01:34

If successful to any degree, or even if you realise why it was not,
then please report with some notes as this and similar are on my list.

well i got an immiscible phase that smells of oranges (but in a weird way, hard to describe). i did in total 2 batches, from 1.1kg of peels i got 13ml of limonene(i forgot to weight the vial so i used the density of limonene found online to get a rough estimate) 1% of the total mass, this is consistent with the result that NileRed got on a smaller scale.
i would need to check the boiling point to be sure, maybe by using a test tube i could be able to do it (i don't have really small glassware at the moment)

[Edited on 18-11-2018 by Ubya]

JJay - 19-11-2018 at 10:07

I constructed a fume hood. It's functional but a little too amateurish for the fume hood thread lol

Ubya - 19-11-2018 at 10:58

well the important thing is that it'd soing its job, you'll surely upgrade it in tbe future, but if you need it now i don't see why not. i've been working on mine for 3 years (just a few minutes in the weekends) but still needs a sash and a venting system, so it's useless as a fumehood, quite useful as a bench though.

ps cool idea using plastic wrap as window

JJay - 19-11-2018 at 11:50

It's vinyl, so it's reasonably solvent resistant and doesn't burn easily.

Plunkett - 22-11-2018 at 12:30

My scale quit working so I gave it a viking funeral à la thermite.

arkoma - 22-11-2018 at 14:09

Quote: Originally posted by Plunkett

My scale quit working so I gave it a viking funeral à la thermite.

LMAO

Ubya - 24-11-2018 at 10:41

hoping to get carbon quantum dots in a few hours
3g gelatin
6g water
1 drop HCl 32%
closed tight and cook at 180°C for 6 hours

still 4 hours to go

Ubya - 24-11-2018 at 14:25

well it worked

Housane - 24-11-2018 at 14:30

Hi Ubya,
i want tomake lemonine and was wondering how fine to grate the peel andx what distill temp.

Also what aved you just dpne i dont understand

thanks

Ubya - 25-11-2018 at 04:15

Quote: Originally posted by Housane

Hi Ubya,
i want tomake lemonine and was wondering how fine to grate the peel andx what distill temp.

Also what aved you just dpne i dont understand

thanks

i used a potato peeler to get just the flavedo (the part with oil glands), i then blended the peels with a blender, you don't really need a paste, more something like granulated nuts (do you get the idea?). the distillation temperature is not critical, i mean you are making a steam distillation so it will be close to 100°C, just don't use super high heat or you could burn the peels inside they flask if the are in direct contact with the bottom.

for the last thing i did i just made some carbon quantum dots (nanoparticles that have the color dependent on their size) using hydrothermal carbonization. i built a pressure vessel with pipe nipples and caps, filled with water and gelatin to half of the reactor volume, and heated it to 180°C (the vapour pressure of water at 100°C is 1 atm, at 180°C is around 10 atm) so in the vessel i got water boiling at 180 degrees and 10 atm. the end product is literally char, but some of the carbon is in nanoparticle form

[Edited on 25-11-2018 by Ubya]

[Edited on 25-11-2018 by Ubya]

Abromination - 25-11-2018 at 12:30

Made some sulfuric acid today by NurdRages method of electrolysing copper sulfate. Very time consuming and frustrating. If the cathode isnt in just the right place, copper won't deposit on it. I have gone through a lot of pencil lead too. I have about 100 mL of diluted acid now though.

Herr Haber - 27-11-2018 at 04:57

I washed the dishes without my protective equipment.

arkoma - 26-12-2018 at 19:40

Azeotropic nitric Acid today. Diluted rooto and 100gms potassium nitrate. 62 gm azeotropic acid, and the same of fore run. A success..

Σldritch - 28-12-2018 at 09:20

Quote: Originally posted by arkoma

Azeotropic nitric Acid today. Diluted rooto and 100gms potassium nitrate. 62 gm azeotropic acid, and the same of fore run. A success..

Coincidentally that was exactly was i was doing that day too but i used the aqueous Sodium Bisulfate method. I got about a hundred ml, only about 40% yield; i think a lot is lost in the Calcium Sulfate, it smells strongly of nitric acid.

hacker - 29-12-2018 at 02:08

I hydrolized some ASA to salicylic acid with hydrochloric acid. I followed UnintentionalChaos' procedure. I obtained 450.11 grams of salicylic acid product. If pure, the yield from pills is 72%. It is a powder. The powder consists of tiny crystalline needles. There are lumps in it. It smells faintly of acetic acid. I believe it contains ASA impurities.

I think it is pure enough for making phenol.

mayko - 2-1-2019 at 21:19

https://www.youtube.com/watch?v=aqR4_UoBIzY

88% Lactic acid, 150 mL

I have some of this fizzing with some basic copper carbonate right now on its way to copper lactate.

Quote:

Also, from the grocery store: two bottles of Elmer's glue and a box of cornstarch

I tried this out - it took 3:30 direct MAPP gas flame to burn a pinhole through a thin spot in the 1/4" piece I tested first! The side not facing the torch was otherwise only warm to the touch.
One thing I'd recommend if you try this is to spread out a bit of starch to work the material in like pizza dough - otherwise it sticks and doesn't easily come loose

Ammonium permanganate

TheMrbunGee - 9-1-2019 at 21:18

Made a Video, if interested.

30g of potassium permanganate is dissolved in 120 ml 60°C water, a 50% excess of 15g ammonium chloride is dissolved in 30 ml 60°C water, solutions are combined while stirring. Solution is cooled to 0°C and formed crystals are filtered, washed and dried. With sloppy washings 92% yield. 24g of 26g theoretical.

Checked various properties.

Herr Haber - 11-1-2019 at 14:03

Checked various properties.

The trails from big cristals are beautiful !
Interesting tests in general too. Great vid

Sulaiman - 11-1-2019 at 14:38

Made a Video, if interested.

I've only got as far as the credits,
my daughter not wearing her spectacles read 'Ammonium Permanganate Synthesis' as
Armenian Pomegranate Synthsis

EDIT : Nice video, interesting oxidiser, I may try similar myself sometime.

[Edited on 12-1-2019 by Sulaiman]

TheMrbunGee - 11-1-2019 at 20:33