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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Is there a better way for filtration of liquid tin?
Here is part of my idea for removing an excess of tin from an alloy:
The alloy will be necessary for further experiment, it has not been characterized yet, AFAIK. I believe it will contain robust ...
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Relative Error vs. Absolute Error in different glassware
Why, for some glassware (such as graduated cylinders and burets) is the absolute error constant throughout the instrument and the relative error is dependant on the measured volume, while for other ...
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Reflux under inert conditions
If a procedure calls for reflux under inert conditions, is it alright if I let nitrogen as protective gas run through the condenser for about 15 minutes, and then attach it to the flask with pre-...
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Instructions for handling toxic liquids
I would like to know what precautions should be taken when handling liquids like trichloroethylene, tetrachloroethylene, dichlormethane, and mercury. Of these, which is most toxic?
I have seen people ...
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Solvents for tartrates / tannins that won't attack glass
At the bottom of my wine decanter (which due to its shape is fantastically hard to clean mechanically) a layer of reddish brown precipitate forms. I believe this is probably potassium bitartrate ...
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Will Triflic Acid Damage PTFE?
We recently received an ampule of trifluoromethanesulfonic acid (TFSA) for use in upcoming experiments in the lab. Once we open the ampule we'll need a bottle to store it in. We have amber glass vials ...
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How to remove glass shards out of a tiny hole to fit capillary tube?
This is oddly specific, but I am having trouble making the setup work for my electrochemical cell. We're doing Scanning Electrochemical Cell Microscopy (SECCM)* and the device has a capillary tube fit ...
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Is it safe to use borosilicate lab glass as an autoclave?
I'm attempting to do a one-pot synthesis that requires autoclaving the chemical mixture. I thought this process would be greatly simplified by using the lab glass itself as the autoclave in situ ...
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What is the accuracy of medical syringes?
I am interested in both low and high volume syringes.
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Changing of water in the Rotary Evaporator RC 600 affecting its performance
The KNF Rotary Evaporator RC 600 as shown above has not had its water(from the bath) changed for quite some time now(my best estimate is roughly 2 months). There is also a dead fly in it. Yet it is ...
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Why are amber bottles used to store Water for HPLC?
Image Source: https://www.calpaclab.com/water-hplc-spectro-grade-4-liter-bottles-case-4/ted-ws2211-001
When ordering HPLC/Spectro grade Water for HPLC from certain vendors(not all), it comes in an ...
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Is there any way to use syringe pumpe in pumping flow
I want to use syringe pump to pump water at 0.82 ml/min for 30 min ? Is that possible ( I read some paper use that but don't know how ?)
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The accurate use of a "Mortar and Pestle" and its grinding patterns
At my internship, I was asked to use a mortar and pestle. I placed a pigment sample in the mortar, and was asked to apply a downward pushing motion in a circular pattern with my pestle. I kept a firm ...
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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 does the blue square on a volumetric flask mean?
What does this blue square on my volumetric flask mean? I see such squares/rectangles on a numerous other flask brands as well. What is its purpose?
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Why don't oils use plastic droppers?
As shown in the picture, most cosmetic oils and serums make use of glass droppers. However in the chemistry lab, scientists often also use reusable plastic droppers as well. My question was that, ...
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What do double rings mean on a pipette?
In this image of a pipette, what do the double rings mean?
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Why does glass etching cream contain sulfuric acid?
The MSDS for various glass etching creams all show that they're primarily composed of 4 substances (the composition percentages vary):
Ammonium Bifluoride - 20 - 40%
Sodium Bifluoride - 5 - 10%
...
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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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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 is this gel byproduct of acetylsalicylic acid recrystallization?
I did a very simple acetylsalicylic acid synthesis from salicylic acid and acetic anhydride (with phosphoric acid as a catalyst). After rinsing, filtering and drying the product I dissolved it in ...
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When Should you use grease to lubricate ground glass joints?
I am getting ready to try steam distillation following this guide which references an earlier chapter which says "If using grease as recommended by your instructor, lightly grease all joints.&...
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Why potassium carbonate breaks glass when heated? [closed]
I have been studying about desiccants for a while and testing some inorganic salts, including calcium chloride, sodium sulfate and potassium carbonate. When they get enough moisture from air, I ...
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How can I read an Anschütz/Bennert manometer and how can I make sense of it?
Recently I have come across a mercury-filled manometer for vacuum distillation that somewhat resembles a U-tube shaped manometer, but with one arm sealed and completely filled with mercury. Searching ...
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How to attach soft tubing to glass
I plan to do some amateur chemistry with some basic equipment. I've watched hours of youtube videos for how to bend and polish glass tubing and push it through rubber stoppers, and I've seen diagrams ...
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Is it critical to match vacuum pump oil to specific pump?
We have rotary vane vacuum pumps of many makes, models, and ages, but superficially they seem remarkably similar. Each has a recommended pump oil (that is, if we can find the documentation); often ...
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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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How can I remove water vapor from an airstream without a cold trap?
I'm trying to perform vacuum distillation at home with a rotary vane vacuum pump.
In order to not ruin my vacuum pump, solvent vapor (in my case, water) should be removed from the air before it ...
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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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How can I get this glass stopper out? Need troubleshooting!
I placed a glass stopper in a $\pu{100 mL}$ round bottom flask while my solution was still warm and let it cool overnight. Now I think I created a vacuum seal and I can’t force the stopper out to ...
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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 ...
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Soxhlet extraction condenser - addition of compound to refluxing setup
I've never used Soxhlet apparatus before and I have troubles understanding how to properly perform the following step from my protocol:
To a gently refluxing suspension of 1 g Lithium aluminium ...
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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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Using a vintage lab balance scale with a chain-dial
I have obtained an an antique Philip Harris balance scale in good, but condition aside from a lot of corrosion on the brass. I can't find a model number on it and am not sure of it's actual age, but I ...
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What is the sample density used for a buoyancy mass correction?
For a lab exercise to calibrate volumetric glassware I was given the follow equation to correct weighings for the density of air:
$$m_\mathrm{c} = m_\mathrm{s}\,\frac{1 - \rho_\mathrm{a}/\rho_\mathrm{...
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Can I use a mechanical pipette to transfer strong acid?
I am an undergraduate student majoring in physics. I am looking for the best method to accurately measure the volume of strong acids like hydrobromic $(w(\ce{HBr(aq)}) = 48\,\%)$ and hydroiodic $(w(\...
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Is Silica Gel fit for Ultra-High Dessication?
I had the (perhaps wrong) notion that silica gel wasn't that strong of a dessicant, especially compared to CaO, MgO, CaSO4, H2SO4, KOH, Mg(ClO4)2), but I've been exposed to information* that might ...
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How does functionalized activated charcoal work?
If I understand correctly it is possible to trap stuff inside activated charcoal (AC) pores to give it specific retention properties (by exposing it to functionalizing compounds while heated to open ...
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Would a 0.3 micron filter be effective in blocking formaldehyde fumes produced by curing cyanoacrylate?
I’m looking into purchasing a mask that blocks particles larger than or equal to 0.3 μm in size. I’m hoping it blocks the formaldehyde fumes produced by curing cyanoacrylate.
How effective such mask ...
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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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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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Which vessel materials are compatable with magnetic stirrers?
I am shopping for some metal pans and beakers for use on my magnetic stirring hotplate. I do not want to block the magnetic coupling of the stir bar. The question is which common alloys are compatible?...
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Connect glass tubes to a graham condenser
I am currently making a syphon coffee maker such as this one:
However, I find that all the silicon tubing used on this image between the condenser and the boiling flask / between the condenser and ...
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Purpose of an Iodine Flask
Is there any specific reason why Iodine Flasks are used instead of Erlenmeyer Flasks when doing Iodine Determination tests?
Iodine Flasks are quite expensive when compared to Erlenmeyer Flasks.
Does ...
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Experimental setup
I would like to know your opinion regarding the setup of a system for oxygen purging with nitrogen. Before ordering the necessary materials, I'd like to be sure if this setup is feasible or if it can ...
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How should you report measurements and uncertainty for a measuring cylinder with 0.5 mL graduations?
I understand that a common convention is to report the uncertainty of an analogue instrument as plus or minus half of the smallest scale division.
By this logic, a measuring cylinder with $\pu{0.5 mL}$...
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How can I clean solid sulfur and its oxides from test tube?
I was experimenting with sulfur few years ago. The test tube I used for that purpose has still sulfur stuck onto it. I was searching for a way to dissolve it.
I found an idea to try warm acetone. ...
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What material should my evaporation dishes be made of to combat static charge buildup?
I have great difficulties moving very fine powders from a drying dish (glass) into small plastic containers using a metallic spatula due static charging. I have to scratch a lot inside the glass ...
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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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Best bet for separating fused glassware
I have a sintered glass funnel stuck in a flask with a 24/40 ground glass joint.
I regularly used this glassware to process very dilute solutions of uncured photopolymer resin dissolved in ethanol. ...
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