Sciencemadness Discussion Board - Lab tips & tricks

Lab tips & tricks

Mabus - 6-4-2018 at 14:53

While the Improvisation page is good for offering advices on various lab items and jerry-rigs, as are the cleaning, handling and disposal articles, I think a page for other lab tips is needed, like say, lab space, organization (space and time), less known properties of lab items or reagents, ventilation, cleaning, lab item storage, how to do a proper setup or a more effective one, shortcuts, maintenance, etc. you get the picture.
The article is here, there is still plenty to modify and improve, and if you can't edit, write your ideas in this thread. More is better.

Sulaiman - 6-4-2018 at 15:53

"Place the reagent storage shelves/closet close to your bench, but away from the kitchen sink"
to
"Always keep chemicals and chemistry separate from food and cooking"
___________________________________________________________
Eyewash Station ... really ?
How many of us have an eyewash station ?
Is it a prerequisite for hobby chemistry?
_____________________________________________
"Keep the glassware in drawers, separated by types (beakers in a drawer, condensers in another, etc.)"
Why can't I use my stackable transparent plastic containers ?
_______________________________________________________
"Never keep your glassware and fragile objects on a shelf nailed to the wall, as there's always the risk of falling and breaking your lab items, always keep them "grounded""
My shelves never fall down and being attached to the wall makes them stable.
______________________________________________________________
"Place all of your small metal items (keck clip, scoopula, spatula, wire gauze) in one drawer, while larger items (clamps, jacks, tripods) in separate locations"
I prefer to group my stuff by function rather than material.
_______________________________________________
How many here use a lab coat ?
________________________________________________
"When doing a reflux reaction that needs distilling afterwards, use a Liebig condenser as a fractionating column in a distillation setup, then connect the output of the distillation condenser to the bottom of the Liebig to reflux."
... fractionating column ? ... needs clarifying.
______________________________________
"If you're distilling compounds that attack the rubber seals of on ordinary thermometer adapter, instead of getting fancy ground glass thermometers or a teflon adapter, wrap one layer of teflon tape wrapped around the thermometer, then just poke it down into the adapter and thread the cap on top, sealing the teflon against the glass"
A) you could have your thermometer smash into your flask below like that
B) do you trust that to seal against e.g. HCl, Cl₂, vacuum etc.?
I don't think I would.
________________________________________________
more if required.
you have been too specific, not generally applicable in my opinion.
___________________________________________________

j_sum1 - 6-4-2018 at 16:06

Hkparker (or was it mystYt32) did a nice little video on this topic.
My contribution: masking tape. The rolls can act as stands for RBFs.The tape is good for labelling.

Ubya - 6-4-2018 at 16:07

Don't keep oxidizers and organic solvents in the same place,
5kg of potassium nitrate near a few liters of acetone, toluene, ethanol and petroleum ether seems a wonderful idea (yes i kept all of these in the same cabinet until i thought it wasn't a great idea at all)

Mabus - 7-4-2018 at 00:35

@Sulaiman I mostly added stuff from both SM threads and other chemistry sites most from professional chemists. I'll alter some of that text to fit better with out line of work.

EDIT:

Quote:

"When doing a reflux reaction that needs distilling afterwards, use a Liebig condenser as a fractionating column in a distillation setup, then connect the output of the distillation condenser to the bottom of the Liebig to reflux." ... fractionating column ? ... needs clarifying.

OK, upon seeing the original text, I too admit I didn't quite understand what the person meant, so I'll just replace it with something else

Quote:

"If you're distilling compounds that attack the rubber seals of on ordinary thermometer adapter, instead of getting fancy ground glass thermometers or a teflon adapter, wrap one layer of teflon tape wrapped around the thermometer, then just poke it down into the adapter and thread the cap on top, sealing the teflon against the glass"
A) you could have your thermometer smash into your flask below like that
B) do you trust that to seal against e.g. HCl, Cl2, vacuum etc.?
I don't think I would.

The idea is that that you replace the silicone rubber ring with one or more layers of PTFE tape, and while the guy said one layer should be enough, more might be needed depending on the diameter of the thermometer or the inner bushing adapter. Not seeing why it won't hold, PTFE tape is very soft and deforms easily, it should hold.
While it's true that thermometer adapters (or bushing adapters with screw cap) are unsuitable for vacuum work (and finding a thermometer with a ground glass is a pain in the ass these days), I don't see why this method couldn't work when distilling stuff that contains HCl, Cl2, Br2, NO2, as in the past I've used PTFE tape successfully to seal bottles containing fuming nitric acid and iodine for long periods of time, and was pretty effective.

[Edited on 7-4-2018 by Mabus]

short answer

Sulaiman - 7-4-2018 at 04:10

I do not think that you should pass on tips that you have not tried personally.

JJay - 7-4-2018 at 04:28

Whenever you spill sulfuric acid over valuable electronic equipment, pour dry potassium bicarbonate onto the spill.

It is suggested that you end the experiment immediately and unplug the equipment, then wipe down the area rather than simply spraying water on top of the potassium bicarbonate and shocking yourself repeatedly.

Oh, and I use a lab coat sometimes but usually only with reagents more dangerous than concentrated sulfuric acid. Really, it's probably a good idea to use one whenever handing reagents more dangerous than universal pH indicator.

[Edited on 7-4-2018 by JJay]

crystal grower - 7-4-2018 at 05:15

I started using lab coat after destroying sufficient amount of T-shirts

Mabus - 7-4-2018 at 09:00

@Sulaiman In that case I shouldn't have written the article, since more than half the info is from the forum chemists and I haven't done it myself.

What I'm trying to say is that just because you done it yourself and it worked, doesn't mean it's the ideal path. For example, I see in plenty of YT videos chemistry professors handling alkali metals with gloves, while in other places (my former university, this forum, etc.) we're always told to handle alkali metals without gloves and use either tweezers or spatulas. If I followed my professors advice, I'd shouldn't use gloves, but had I worked with the other professors, I should have. So which is which? Who do I trust? That's why I wrote the article, to pool all the tips from all kinds of chemists with different experience and compare them.

[Edited on 7-4-2018 by Mabus]

happyfooddance - 7-4-2018 at 11:00

Quote: Originally posted by Mabus

Unless your caps are made out of an inert material, they will probably turn to dust (along with any plastic keck clips) if you try this method with HCl, Cl2, etc. At least they did with me. These gasses are escape artists.

Also, how are screw top thermometer adapters not suitable for vacuum? I use them all the time, never have had an issue.

Mabus - 7-4-2018 at 11:36

Quote: Originally posted by happyfooddance

Quote: Originally posted by Mabus

Weird, I must have a shitty screw cap then. Couldn't get stable vacuum last time I tried that.
I've also included a small disclaimer to that tip, to avoid any confusion in the future.

happyfooddance - 7-4-2018 at 12:48

Quote: Originally posted by Mabus

Weird, I must have a shitty screw cap then. Couldn't get stable vacuum last time I tried that.
I've also included a small disclaimer to that tip, to avoid any confusion in the future.

I would try it with a variety of different o-rings, having the right sized ones make all the difference. Also, test your thermometer cap alone; doing it while you are set up to distill (with 4 or more ground glass joints in the mix) makes troubleshooting many times more difficult.

I do however, always use ptfe tape around the o-ring, like you suggest. I have distilled azeotropic HCl many times like this with no problems, but dry HCl was totally different, every one of my caps broke into several pieces. When distilling a liquid slowly (like one should), vapor doesn't really make it up to the thermometer cap, so that also might explain why it works okay for the 20.2%.

Sigmatropic - 8-4-2018 at 03:18

Screw top thermometer adaptors are not suitable with vacuum because the thermometer can be sucked into the apparatus. In my case the thermometer was intact but the vigreux column not so much

LearnedAmateur - 8-4-2018 at 03:34

Quote: Originally posted by j_sum1

The rolls can act as stands for RBFs.The tape is good for labelling.

Oh yeah, I use a roll of Gaffer tape for resting my 250mL RBF and smaller flasks sit quite quite comfortably inside without spilling. Thought I was the only one to be honest. Barring that, if you’ve got >100mL beakers not in use, they can serve the same purpose.

[Edited on 8-4-2018 by LearnedAmateur]

Sulaiman - 8-4-2018 at 03:45

So far I have not used more than two or three RBFs at a time,
so I use 'spare' retort clamps to hold them if required.
The one time that I used many flasks at once I used Florence/Florentine flasks.
(from an eBay bulk buy of surplus/used glassware)

Retort clamps are also very useful for holding washed glassware up-side-down for draining/drying.

DavidJR - 8-4-2018 at 10:14

Quote: Originally posted by LearnedAmateur

Quote: Originally posted by j_sum1

The rolls can act as stands for RBFs.The tape is good for labelling.

Often when I've used a spare beaker as a flask stand the flask tips over. Glass on glass just isn't a lot of friction. Rolls of tape work better.

Plunkett - 8-4-2018 at 10:49

I use an aquarium air pump and vinyl tubing to force air through wet flasks and condensers to make them dry quicker; a slightly less effective method is to prop the glassware upside down over a floor vent. In either case, the glassware dries significantly faster than just leaving it to air dry.

Mabus

Sulaiman - 8-4-2018 at 11:19

The O-ring size is important,
I have a screw-top thermometer adapter and a screw-top still head adapter,
as supplied with my cheap distillation kit.
I cannot use the thermometer supplied with the kit (c5.5mm dia.) as it will slip,
but my 'normal' thermometers (c6.5mm dia.) fit very well.

LearnedAmateur - 8-4-2018 at 11:56

Quote: Originally posted by DavidJR

Often when I've used a spare beaker as a flask stand the flask tips over. Glass on glass just isn't a lot of friction. Rolls of tape work better.

I only use 50mL beakers as a stand for 100mL flasks when they’re empty, I meant placing them inside a beaker with a larger diameter than the flask so that the joint/mouth rests against the rim. 250mL beakers should house 100mL RB and pear flasks quite snugly, I would test to make sure but I don’t actually have any, the one I did have shattered and went in the bin months ago.

Mabus - 8-4-2018 at 13:09

Quote: Originally posted by Sigmatropic

Screw top thermometer adaptors are not suitable with vacuum because the thermometer can be sucked into the apparatus. In my case the thermometer was intact but the vigreux column not so much

I never got to that part since I couldn't get a vacuum

@Sulaiman I purchased my thermometer adapter separate from the thermometer exactly for that reason (I could have bought a distillation kit, but I didn't want to get some unexpected surprise).

JJay - 8-4-2018 at 23:17

I've used screw top thermometers with vacuum dozens of times without issue... it is essential to make sure that the thermometer is secure before and preferably also after applying a vacuum.

Tsjerk - 9-4-2018 at 05:19

Always wear a lab coat and goggles, you will be happy when it saves you that one time when the accident came out of nowhere. I have been lucky to be wearing them that one time I needed them. It came out of nowhere while working with stuff less dangerous than pH indicator

Texium - 9-4-2018 at 06:47

Mabus, Dr. Bob should still have some 10/18 GG thermometers if you're looking for one. I bought one from him recently, as I've had 10/18 jointed still heads for years but never a thermometer to go with them. Up until now I just stuck a normal thermometer in there and held it in place with a rubber anti-roll ring and copious PTFE tape.

Filtration tip your professors probably won't tell you/ Filtration tip for purity OCD(mysophobia)

fusso - 12-5-2018 at 12:40

Think about which part of the rxn mixture you want before taking a piece of filter paper out of its box:

If you want the filtrate: fold the 'up' (dustier) side inwards and immediately put it in a freshly cleaned funnel to prevent dust being washed into the filtrate.

If you want the solids, remember which side is down. Leave the 'down' side facing down. Only flip it up side down immediately before filtration and use the cleaner 'originally down' side to catch the solids. Best to also cover the whole filtration setup with air-permeable material like paper, cloth.

VSEPR_VOID - 30-6-2018 at 09:32

Quote: Originally posted by crystal grower

I started using lab coat after destroying sufficient amount of T-shirts

Same...I am up two two shirts and a pair of pants.

Sigmatropic - 30-6-2018 at 10:36

When finishing a liquid-liquid Iextraction gently swirl the sep. funnel to knock down last droplets from the walls.

When encountering emulsions gently heat the emulsion from the outside of the sep. funnel with a heat gun. The increased temperature increases the molecular movements causing the emulsion to break up faster. (note that occasionally cooling is beneficial as some but not all solvents become (more) immiscible below a certain point, see for instance the bahavior of MeCN-H2O. Sometimes solvents become less miscible by increasing the temperature (as is described in Vogel's). I do not know how ternary systems behave but I had the feeling that the DCM-MeCN-H2O system gave better and faster separations at or below 0C.

And finally for those ocd on purity, use the stopcock of a sep funnel to capture the thin film present at the interface and remember to remove the bottom layer through the bottom and the top layer through the top (after you've drained the bottom layer obviously).

JJay - 14-9-2018 at 08:21

I often use a reflux condenser above the distillation receiver, especially when distilling volatile chemicals. Like this: http://www.prepchem.com/synthesis-of-p-toluquinone/

I think this is fairly common.

[Edited on 14-9-2018 by JJay]

macckone - 14-9-2018 at 14:44

Eyewash: it doesn't have to be a professional eye wash.
A squeeze bottle of saline from the contact lens section of your local store works wonders. But always have something to use as an eyewash, even if it is just a bottle of water.

O-rings for thermometer adapters: Automotive O-rings that are suitable for E-85 and regular gas are made of viton. This is compatible with most things except ketones, and even then they are cheap to replace, most automotive stores carry a variety. You can get teflon o-rings as well, they are literally more expensive to ship than buy (US$ 1.30 for 5). A ground glass thermometer well never has o-ring problems and you can use regular cooking oil as a heat transfer solution without worrying about contamination.

A better option for the use of teflon is to wrap the thermometer below the adapter and then pull it up to seal it and protect your 25 cent o-ring.

Lab apparel: Jeans and a long sleeve shirt are a minimum. Protect your arms. Wear boots not cheap shoes. Pretend like you are cooking and moving around hot oil. A lot of lab chemicals aren't nearly as bad as hot oil but working like it is will save a lot of trouble later.

Fires: If you have a fire, you did something wrong. BUT, you should have appropriate materials to put out the fire you are working with. Baking soda works better than water on most organics as it releases CO₂ and doesn't spread the fire. Oil or sand work better on metal fires than water. But you may need to extinguish the oil after you put out the metal.

nimgoldman - 14-9-2018 at 17:15

Quote: Originally posted by VSEPR_VOID

Quote: Originally posted by crystal grower

I started using lab coat after destroying sufficient amount of T-shirts

Same...I am up two two shirts and a pair of pants.

Same here :'D Lab coat is not a piece of clothing, rather a line of defense, something to quickly remove and throw away when compromised with some nasty chemical.

The material (cotton) is especially good in absorbing stuff.

nimgoldman - 14-9-2018 at 17:32

Improved thermometer.

It's simply the TM-902C probe inside a thermometer adapter filled on bottom with thermal conductive paste and some glass wool and duct tapes to keep it all in place. This improves response and accuracy of the readings.

Credit goes to ChemX YouTube channel.

Ubya - 15-9-2018 at 01:11

i did a similiar thing some time ago when i broke my only mercury thermometer, i used a pipette, melted the tip and inserted the K-therocouple to its bottom, the glass there is thin so the heat capacity is small, the temperature reading is really fast upon changes in temperature. i think that with all that conductive paste you have quite some heat capacity, less is better to get a fast response

nimgoldman - 15-9-2018 at 07:38

Quote: Originally posted by Ubya

i did a similiar thing some time ago when i broke my only mercury thermometer, i used a pipette, melted the tip and inserted the K-therocouple to its bottom, the glass there is thin so the heat capacity is small, the temperature reading is really fast upon changes in temperature. i think that with all that conductive paste you have quite some heat capacity, less is better to get a fast response

Good idea thanks. I have lots of pasteur pipettes but unfortunately no way to melt them. I guess a butane torch lighter wont be hot enough right?

I needed an adapter instead of rubber stopper because sometimes I distill aggressive stuff and the rubber would degrade. But I guess something similar can be done with an air inlet tube.

nimgoldman - 15-9-2018 at 07:46

One more tip is to have certain common chemicals in a freezer, especially brine, sulfuric acid and solvents like acetone.

Brine can be used to chill a solution below 0 °C, it's more effective than an ice bath and is always liquid so easy to recycle/reuse.

Pre-chilled sulfuric acid is practical for dilution - in most cases adding it to a reaction mixture is highly exothermic so the pre-chilling helps a lot.

Chilled solvent (e.g. ammonia solution, acetone, ethanol etc.) is practical for washing products.

It also comes in handy to have distilled water frozen in ice cubes (amount can be weighed). This way you can pour hot stuff on it or quench a reaction without having to set up an ice bath beforehand.

I have a portable 30L car fridge/freezer for lab use. It has a compressor and thermostat so you can even set temperature down to -20 °C.

...or and a microwave is probably the fastest way to heat up water. It saves lot of time.

[Edited on 15-9-2018 by nimgoldman]

VSEPR_VOID - 19-2-2019 at 23:16

Use a glass stir rod to help pour liquids. Keep several scupulas on hand and have one specifically set aside for heating substances.

Check thrift stores for cheap equipment like compressors, pumps, glass containers, fridges, power supplies, heating elements, and even depression glass.

Keep a UV light in your car for finding interesting minerals or depression glass.

Do reactions on a bulk scale if you are going to be using the product often. This includes making nitric acid, diethyl ether, or dry solvents. This boosts yield as you lose less to mechanical losses.

Make stock 1 M solutions of test solutions and titrations and keep them in bottles with droppers. Its also very ascetically pleasing.

You can cut old aerosol cans and propane tanks open to use as reaction vessels or chambers.

SWIM - 20-2-2019 at 15:34

Quote: Originally posted by nimgoldman

Quote: Originally posted by Ubya

I just melted a Pasteur pipette over the gas burner on my stove, so I'm pretty sure almost any torch would do the trick.

I haven't had any luck melting PYREX that way though, but Pasteur pipettes are soda glass I think. (Sure does melt like it.)

PirateDocBrown - 20-2-2019 at 19:27

Cut some thick rubber tubing to cushion iron rings that hold sep funnels. You don't want a funnel breaking when full of fluids.

It always makes my teeth stand on edge when I see glass-on-iron in chem videos.

PirateDocBrown - 20-2-2019 at 19:29

Use sealed off pipettes or small test tubes to make ampoules to hold volatile or air/moisture sensitive compounds. Much cheaper than buying ampoules, too.

happyfooddance - 21-2-2019 at 11:04

Quote: Originally posted by SWIM

I seal Pyrex and Kimble capillary tube tips with a stove flame. And on boro Pasteur pipettes you can seal both sides with this sort of flame (you will need to thoroughly pre-heat your crimping tool for the broad side though).

Boro Pasteur pipettes can be sealed at the tip with a bic lighter, even!

morganbw - 21-2-2019 at 17:16

Quote: Originally posted by happyfooddance

Quote: Originally posted by SWIM

I have done some of the capillary tubes with a bic for shits and giggles but have never tried a boro glass. Interesting info

arkoma - 21-2-2019 at 17:50

the rubber "bumpers" on the magnet off old subwoofers make excellent RBF holders

RogueRose - 21-2-2019 at 19:26

Quote: Originally posted by arkoma

the rubber "bumpers" on the magnet off old subwoofers make excellent RBF holders

I doubt many people are going to have that available but it would probably work well.
I'd bet most people have some old garden hose, vinyl tubing or even old inner-tube (car, tractor, bike, etc). I'd think that all of those would work well. Failing that, I don't see why you couldn't use paper towels (fold it over a few times and put it between the glass and metal.

arkoma - 22-2-2019 at 18:44

Pulloff the back of an old subwoofer, nice and "grippy" from being rubber

That's One Less!!

sodium_stearate - 23-2-2019 at 08:57

Nice work! That is one less of those annoying
speakers that always go BOOM BOOM BOOM in the night
as some dweeb drives around in his ghetto blaster! :cool:

SWIM - 24-2-2019 at 11:56

Quote: Originally posted by morganbw

Quote: Originally posted by happyfooddance

Quote: Originally posted by SWIM

I have done some of the capillary tubes with a bic for shits and giggles but have never tried a boro glass. Interesting info

I have checked my big box'O Pasteur pipettes, and they are in fact boro, as happyfoodance's are.
I just assumed they weren't because they melt really, really easily.
Must just be the thinness and fine point that makes em melt so nice.

WangleSpong5000 - 2-3-2019 at 16:43

Wear safety glasses fucking always, have a fire extinguiser on hand of the correct type, use boiling chips and never take your eyes off a distillation, or at least keep an eye on it

TriiodideFrog - 2-10-2020 at 01:47

You can replace boiling chips with some acid-washed sand and always wear safety equipment. To be honest, you can attempt to extract some chemicals from Over The Counter products, although the yield might not be as good.

draculic acid69 - 26-10-2020 at 06:09

Quote: Originally posted by Sulaiman

The O-ring size is important,
I have a screw-top thermometer adapter and a screw-top still head adapter,
as supplied with my cheap distillation kit.
I cannot use the thermometer supplied with the kit (c5.5mm dia.) as it will slip,
but my 'normal' thermometers (c6.5mm dia.) fit very well.

I'm wondering if water glass can be used as filler/glue to just seal the thermometer
Into The thin screwtop neck.or if I can just melt the t
screwtop and thermometer into each other.i think it could be done without
overheating the thermometer.maybe a very thin Pyrex filler rod is needed.

draculic acid69 - 26-10-2020 at 06:11

Quote: Originally posted by Mabus

@Sulaiman In that case I shouldn't have written the article, since more than half the info is from the forum chemists and I haven't done it myself.

What I'm trying to say is that just because you done it yourself and it worked, doesn't mean it's the ideal path. For example, I see in plenty of YT videos chemistry professors handling alkali metals with gloves, while in other places (my former university, this forum, etc.) we're always told to handle alkali metals without gloves and use either tweezers or spatulas. If I followed my professors advice, I'd shouldn't use gloves, but had I worked with the other professors, I should have. So which is which? Who do I trust? That's why I wrote the article, to pool all the tips from all kinds of chemists with different experience and compare them.

[Edited on 7-4-2018 by Mabus]

I think the guy who said to use gloves is right.

outer_limits - 26-10-2020 at 23:52

Quote: Originally posted by macckone

Fires: If you have a fire, you did something wrong. BUT, you should have appropriate materials to put out the fire you are working with.

One of the first things I bought for lab was 5kg CO2 fire extinguisher. And this my advice for everybody - do not try to save money on protective equipment. It's better to wait for reagents than having your house burned.

Wear eye protection whatever you do when working with toxic/corrosive/irritant chemicals. Even if you don't expect any splash it may occur. I had once that happened after opening the stopcock of sep funnel. Fortunately I use it almost always in fume hood and hood's sash saved my eyes from strongly alkaline solution.

Cut you pH indicator papers to smaller pieces, there is no need to waste entire paper just for one pH check.

Always leave some space below the flask, so you could swap immediately from heating mantle to cold water bath and slow down the reaction.

If you break a plate or mug at home - do not throw it away . Shatter it to small pieces, these are great boiling stones.

Plastic wrap is good for sealing, not as flexible as parafilm but good enough.

If your lab is located in a dusted, dirty space - use plastic wrap to keep it clean.

If there is a moisture - keep your moisture-sensitive reagents in string bags.

Use teflon tape to seal bottles. Teflon tape can be used as an alternative to joint grease. And it's much cheaper than teflon sleeves available to buy in laboratory equipment shops.

Separate your reagents regarding their compatibility - you don't want to keep strong acids with strong bases as well as oxidizers and reducers.

Keep the bottles as low as it's possible. If they fall down from the shelve there is a probability that they could survive without breaking.

[Edited on 27-10-2020 by outer_limits]

Fyndium - 27-10-2020 at 02:51

Fire extinguisher is an absolute mandatory. In some instances it can be replaced with ordinary water hose with for ex garden nozzle that can turn the water into mist. Water mist has an impressive fire extinguishing properties, I've been in fire exercise where we had to put off burning 40' containers. With fire hose, it needs only three bursts of water to suffocate the whole fire.

This requires you to have mains switch directly next to hose or an RCD installed for all the electric equipment to not get electrocuted. Volatile, flammable solvent in for ex case of flask breakage will immediately create immersive flames that can burn down your entire building if you cannot put it away in seconds. Even here I've read multiple occasions where people have broken flasks, beakers and stuff directly on their hotplates by some reason - maybe they were just not properly annealed. CO2 can suffocate, though, so ventilation becomes a vital aspect if it has to be used. Powder extinguisher is an option too.

Sometimes one should also just sit back and think what really cuts costs or trouble. I've concluded that just simply buying various items like thermowells is much more convenient than playing around with all kinds of rubber, silicone or similar plugs.

And I mean buying, because they cost so little. 2€ for thermowell is just nothing. I've literally built another set of labware at my home including all accessories for a few hundred euros.

I use lab jack and install it so I can at any time remove the heating bath completely and if necessary, switch into cooling bath. This is important for quick heat control and can be life-saving in case of runaway.

I also want to keep every apparatus attached to a stand. I've installed permanent threaded rods in my fume hood. Once, over 10 years ago, when I was starting chemistry, I actually crashed an entire distillation apparatus to the floor because lack of stands. Silly me. What surprised me though only the condenser attachment broke and almost none of the process fluid was lost.

TriiodideFrog - 28-10-2020 at 04:33

Yes, I agree that is an absolute mandatory to have a fire extinguisher in your lab. Some compounds cannot be extinguished by water. Some fires might even become worse after adding water onto them ( magnesium fire e.t.c).

Belowzero - 28-10-2020 at 06:31

I use empty tape rolls (cardboard) as RBF stands , very stable and free.

[Edited on 28-10-2020 by Belowzero]

itsallgoodjames - 28-10-2020 at 08:59

Quote: Originally posted by Belowzero

I use empty tape rolls (cardboard) as RBF stands , very stable and free.

[Edited on 28-10-2020 by Belowzero]

I do this as well, it's incredibly useful

[Edited on 28-10-2020 by itsallgoodjames]

Fyndium - 28-10-2020 at 10:48

Quote: Originally posted by TriiodideFrog

Some compounds cannot be extinguished by water. Some fires might even become worse after adding water onto them ( magnesium fire e.t.c).

This is a very important notice. If the material reacts with water, it could cause even more issues. Also extinguishing a fire at any sort of oil bath is a potential for disaster. It is possible to extinguish oil fires with water, but for that you'll need a misting nozzle and experience how to use it.

When working on a project, it is good to make a safety assessment on the materials used or formed during the project, how reactive and toxic they are and have a plan ahead in case of something goes wrong big time.

Rainwater - 22-2-2022 at 16:22

When your distilling above room temp and the condincer gets overloaded easily or your recycled condencer water gets too warm to fast.

Add a horizontal column with air cooling before the liquid cooling

Use a non flammable non reactivate material to insulate the flask and still head.

Rip the heat exchanger out of an old car and pipe it after your condencer to your reservoir.
The one out of my ex's new car seams to work best. Not sure why.
The heat exchanger can be fan cooled with running water over it. (swamp cooler)

Here, I use dust proof ceramic fiber insulation (2200c fire proof) around a 1 liter flask

1in hot water pipe insulation around the still head

An air cooled (dont know the name) column,
and a west condencer.

Distillation is h2o @ 100c
My condencer temp doesnt get above 38 @ a room temp of 20.

An easier way to get distilled water is to use condensation from a dehumidifier

[Edited on 23-2-2022 by Rainwater]

Rainwater - 4-6-2022 at 05:36

Can tlc plate be used to check the purity of inorganic salts and reagents?

For example, with proper solvent selection, could I test something like Au2Cl6 for contamination, say from copper, lead or other metals.

Then maybe test the purity of a product or reagent in the same manner?

Everything I've read only describes interactions with organic substances.

Antigua - 4-6-2022 at 05:42

Actually yes. It's often done as a chromatography presentation. Try taking a large circular piece of filter paper, cut a strip to the middle of the circle, bend it so that the end of the strip can be submerged in your solution and the rest of the circle can rest on top of the crystallizing dish or the beaker. Now capillary force will drive the solution upwards and towards the perimeter of the circle and depending on the RF various colors can be seen or visualized using various stains.
Something like this: