Questions tagged [equipment]
Questions regarding the equipment used in labs (such as flasks, tubes etc.), their operation and maintenance.
243 questions
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Choosing the right condenser
What are the advantages and disadvantages of the various types of condensers commonly found in the laboratory? Obviously more intricate pieces of glassware are more costly but assuming they are all ...
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What benefits do higher-rated NMR tubes provide?
You can buy NMR tubes in a huge variety of qualities, with an equally huge difference in price between the cheapest and the most expensive NMR tubes. They are usually rated for a specific spectrometer ...
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Help me identify this glassware!
I'm a freshly graduated physics and math teacher moved into a small school from the late 1920s. The equipment here is old and confusing, at the very least. I have found many things which I have ...
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what kind of suspension liquid should be used with ferrofluid (so it does not stain the glass)
Please take a look at the following video:
I am working on a new project, and I need to find whats the best liquid to hold ferrofluid inside the glass (or maybe even plastic) container, so that ...
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Does anyone know what this piece of glassware is?
I recently found this piece of lab glass with a jacket and spout. It says eubilicmeter but I cannot find any information about it online and I do not know what it is supposed to do. It is hollow in ...
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pH probe bulb - what is happening within the glass?
I am trying to understand how the glass bulb of a pH electrode of a pH meter works - the glass bulb itself. Not the reference electrode or the rest of the electrode (HCl, Ag/AgCl wire, etc...), the ...
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What is the "blue spirit" (or "red spirit") in mercury-free thermometers?
I surmise it's some kind of alcohol, but is there a standard chemical used for these?
One of them just exploded in my students' lab! It was the kind with blue fluid in it.
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Unknown glassware
I recently found a piece of older glassware in our lab and nobody seems to know what it is. It appears to be some sort of condenser; however, it does not have both the in and out little notches on it.
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Why isn't pressure filtration popular compared to vacuum filtration?
I want to build a DIY vacuum filtration apparatus with a bike pump but it's very difficult to find one the could be easily converted into a vacuum pump. This prompted an idea to simply build a reverse ...
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What's the purpose of this vintage glassware?
I found this glassware in a phytochemistry lab abandoned in the 1990ies. The piece itself was shelved in the storage room, thus probably already obsolete back then.
The device, entirely glass, is a ...
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Conventional heating compared to microwave heating of chemical reactions
In order to try to increase yield of my cross-metathesis, it was suggested to carry out the reaction in the microwave (a lab microwave, not a kitchen microwave).
The rationale for this was that ...
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Safety in handling of concentrated ammonium fluoride
I recently saw a protocol for extracting organic materials that are bound in the silica matrix formed by diatoms. The extraction protocol used 10 molar ammonium fluoride ($\ce{NH4F}$).
I briefly ...
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What's this glassware?
Can anybody tell me what this glassware with a stem, bulb and long tube is?
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Why does KCl come in amber coloured bottles?
I remember from school that photosensitive chemicals are kept in amber coloured bottles. Is KCl photosensitive? I read up the impurities list on the bottle and it says that it may have bromides too? ...
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What is this Lab equipment?
I want to know the name of this equipment with a sealed graduated tube and the purpose it's being used.
I went through all the results of Google, but I was unable to find this exact equipment. I ...
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Are PTFE stir bars resistant to all lab solvents?
It seems like glass-coated stir bars are a specialty item. Standard stir bars are coated in PTFE. Is PTFE resistant to all typical lab solvents? Or is there a reference to check to ensure it is ...
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What are the plastic connectors called (for glassware)?
I can't remember for the life of me, and google isn't making it easy. e.g. the things labeled 24/40 etc., as in this picture:
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Cleaning a round-bottom flask, especially after distillation
I was wondering, how can I clean my RBF after doing a distillation? Cleaning it with a simple pipe-cleaner or similar cleaner is a headache, due to the roundness of the flask.
Is there a more ...
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How to stop goggles from fogging?
I wear corrective eyeglasses, and because of this, I frequently experience problems with fogging when I wear safety goggles. How can I prevent or reduce fogging?
The safety goggles I use are the ...
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Why do Büchner funnels have no glaze on the top rim?
I have a question about Büchner funnels (just out of pure curiosity). The funnels I have seen have no glaze on the top rim. Actually, the question is why the top end is not glazed. Does it have any ...
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How to remove a stuck stopper from a flask?
How do I remove a stopper that has been stuck in the neck of a 100 mL round bottom flask since I forgot to wipe the neck of the flask. A salt was formed in the 100 mL flask and the stopper ...
user9974
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Why is the outermost part of the Bunsen burner flame not the hottest region?
Why is the blue flame the hottest on a Bunsen burner?
I thought the outermost part of the flame must be the hottest region because of complete combustion of gases taking place there. Where am I ...
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How is polarization of light measured?
Chiral molecules are classified as dextrorotatory (+) or levorotatory (-) depending on whether they rotate plane-polarized light (ppl) to the right or left.
My question is, how is such a measurement ...
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High temperature bath chemicals
I have an electric mantle that I want to bathe reaction vessels at temperatures up to $\mathrm{750^{\circ}C}$. Obviously that rules out oils. What substances are used as bath media at such ...
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What is the fabric in heating mantles made of?
An ordinary lab heating mantle often has a white fabric coating for the flask compartment, which looks like an inorganic fiber:
Image source
I'm pretty sure that for some time in the past ...
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Sintered vs perforated plate Büchner funnels
I just bought a sintered-glass style Büchner funnel for some vacuum filtration tasks. There's two issues I'm having with it:
Filter material, especially activated charcoal, ends up stuck in the glass ...
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What is the scientific term to describe the operation of a bong?
What is the scientific term for the separation of dust particles from air by suction through a specialized flask in a way similar to the operation of a bong?
The thing that led me to this was a ...
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Is it better to use a smaller, more accurate measuring cylinder several times or a larger, less accurate one for the same volume?
I need to measure out 70 ml of liquid.
I have a 10 ml measuring cylinder with a maximum uncertainty of 0.1 ml and a 100 ml measuring cylinder with a maximum uncertainty of 1 ml.
I've calculated that ...
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MacGyvering a sealed tube
Is it possible (advisable?) to make a sealed tube by melting and twisting the end of a borosilicate test tube? One issue that I can think of is that the pressure might be too high if I then proceed to ...
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Water flow in condenser
How should the water flow in your condenser? From the flask to the top of the condenser, or from the top of the condenser back to the flask? I could imagine both: flask to top will fill the entire ...
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What angle limits should apply to Graham condensers?
I have seen Graham condensers set at an angle (perhaps as low as 30 degrees from horizontal). I guessed this wouldn't be a problem because siphoning would clear the condensate. But I recently saw an ...
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How much does the quality of glassware matter, really?
Discussing about the pros and cons of glassware from different manufacturers for chemistry experiments easily becomes a heated debate. Well, that's how it seems if you read the chemistry related blogs,...
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400–430 degrees Celsius heated bath
I want to perform a reaction which needs the temperature to be maintained between 400–430 °C. Since it's the only practical solution, I opted for a heated bath.
I'm looking for a hydrocarbon fraction/...
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Why is there a bulge at the top of my volumetric flask?
Sometimes volumetric flasks are designed with a bulge in the neck right below the stopper opening. What is the design intent of that bulge?
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How to quickly cool a test tube without cracking it?
Is there a way to safely cool a heated test tube quickly without cracking it due to sudden thermal stress in the glass? One thing that I tried was blowing on it, cooling it in slightly lukewarm water ...
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Why are Erlenmeyer flasks shaped the way they are?
The title says it all. We could conceive a good number of other possibilities. Why did Erlenmeyer arrive at this design?
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Use of pipette during experiments for determination of oxygen by Winkler's method
We were performing estimation of $\ce{O2}$ by Winkler's method and we were told by the instructor that while adding $\ce{MnSO4}$ and $\ce{NaOH}$ / $\ce{KI}$ the pipette tip should be well below the ...
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Gold Plating on Glass?
I am considering labware options to handle NaOH solutions at ~150 °C. One appealing idea would be to coat my current glassware with gold. I've read different sources mentioning the possibility without ...
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Why does a glass tube show white bands after being heated with a torch?
When I use a torch to split a glass tube, there's always a hazy white band which appears. Does anyone know what the cause of this is?
It was a hydrogen-oxygen torch. The glass is fused quartz glass, ...
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What is this piece of glassware called?
Here's an image:
The left side is designed to be fitted into a beaker, and it captures gas evolved during a reaction. The right side can be filled with a liquid to then react with that gas. We use ...
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What kind of filter can remove zeolite dust from ethanol?
I only really have high school level knowledge of chemistry, and also I don't really own any lab equipment.
I'm using 3A zeolite molecular sieves to dry ethanol (and sometimes isopropanol) and they ...
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Vacuum distillation apparatus selection and configuration
I want to assemble a "hobbyist-level" vacuum distillation apparatus for extracting small volumes of "typical" solvents (e.g., water, alcohols, ketones, diols).
I already have standard lab glassware ...
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Identifying Name/Purpose of piece of ellipsoid glassware with internal tube?
I recently went to a market in Southern France and found this little piece of equipment for sale along with a whole bunch of other chemistry things. the guy had no idea what it was for or where he'd ...
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What drives the cost of Raman spectroscopy? [closed]
Raman spectroscopy setups are quite expensive- \$10-\$30k seems pretty common. The spectrometer, the probe/fiber cable, and the laser are typically each $3k+.
The spectrometer could potentially be ...
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Why is a volumetric flask shaped the way it is?
A volumetric flask does not look like an Erlenmeyer flask, but has more of a pear shape. Is it just to distinguish more easily between them while they are on the shelf?
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Why did my glass pot explode when I boiled sugar in it and added cold milk?
I decided to try some cooking with sugar and put a glass bowl on the flame with half a cup of sugar in it and some water. After bubbles appeared I stirred the sugar for about a minute and then I ...
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Is there a simple way to distinguish grades of purity for copper metal?
Is there a simple way to distinguish different grades of fine copper purity (on a trace metal basis) that can be carried out in a small lab?
Specifically, I would like to be able to differentiate 4N, ...
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How to identify a blow-out pipette?
Is my pipette a blow-out pipette?
I suspect that it is a blow-out pipette, though the double lines aren't rings. My guess is it is a TC blow-out pipette. It's a big 50 mL pipette, longer than my arm.
...
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