Questions tagged [equipment]
Questions regarding the equipment used in labs (such as flasks, tubes etc.), their operation and maintenance.
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How to store bulk gas products and reagents?
Suppose I'm doing a batch process where an intermediate (non-hazardous) reagent is a gas, and I need to produce and temporarily store something on the order of a cubic meter of it to later feed back ...
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Boiling and Exploding Beaker?
A few days ago, I was creating a solution which involved boiling water. I had two 4L beakers on identical hot plates. After around 10 minutes, the first one boiled. Waiting another 30 minutes, the ...
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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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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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Choosing a vacuum pump for fractional distillation
I have a fractional distillation setup. I would like to purify a small mixture ($\pu{\approx 100-150 mL}$) of high boiling point compounds (between $200$ and $\pu{300^\circ C}$). The one that ...
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What are good lubricants for Bunsen burners?
We've been running into a lot of problems the last several years with our laboratory Bunsen burners becoming jammed and/or corroded. I've just come to find out that our lab tech has been lubricating ...
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Autoclaving certain plastics?
My professor is letting me use the autoclave in the future, but I am a novice. I asked him what materials were safe to autoclave for my notes, materials meaning glass or plastic-ware. He stated, "...
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How to test acid-base reactions under pressure?
I am trying to test chemical reactions, more specifically reactions between an acid and a base, at different levels of pressure.
I would like to know if there is some kind of equipment I can get that ...
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Refrigeration for Cryochemistry −35 °C
I need to cool a tube containing liquid to −35 °C for a cold chemical experiment that will last about a week. The glass vessel I need cooled is 500 mL in volume and will be giving off $\ce{H2S}$ gas. ...
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What is this glassware?
I found this in a second hand store, and I think it has to do with freeze drying. Is there any validity to this assumption? What is this called? Also, the little tuberculina at the bottom are stuffed ...
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opperating a distillation column far from flooding
I know that flooding will ruin the performance of a distillation column. There are many correlations (Eckert, kister, billet, etc.) that will tell you when a column will flood based on your fluid ...
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Bromine Homolysis Using Handheld UV Lamp
I'm trying to investigate the homolysis of bromine for an IB Chemistry (high school) Internal Assessment. To do so, I need a UV lamp capable of splitting diatomic bromine into bromine radicals. Would ...
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Why does my eudiometer have this excess volume at the top?
It looks like this:
The measurements start at 2 mL and the volume remaining in the top seems to be greater than 1 mL. What is the purpose? I am trying to measure hydrogen gas.
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Types of argon gas regulator? [closed]
I have a high pressure bottle of argon gas (99.98 %) that I need to use in an experiment. The problem is that the regulator I have is a generic type that is seemingly optimized for high flow rates (...
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Why does latex tubing become white and brittle over time, especially where it's bent?
Here's a picture of some latex tubing we have in the lab, bought many years ago and stored in a drawer.
What's responsible for the white corners near places where the tubing is bent? Is this ...
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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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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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The weight of a 2cc glass pharmaceutical flame sealed ampoule? [closed]
This is one of the flame sealed type whose neck is broken before use. There seems to be lots of info on dimensions but none with regard to weight.
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Name of round piece of glassware with thin neck?
Found in the lab, it looks like a round bottom flask with an extremely thin neck. Effectively a glass sphere about 60 mm in diameter with what looks like a capillary tube as the neck. Not sure whether ...
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Why laboratory glassware shatter in big pieces?
What are laboratory glassware made up of? This question came up in mind because once I accidentally dropped a test tube and it shattered into big pieces. I observed that it didn't broke into pieces on ...
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Best way to remove Aluminium from "silvered" glass?
Requirement is simple(!) - I have 30mm silvered glass balls that are originally Christmas tree decoration that I want to use in a very unconventional manner in a physics experiment. As far as I can ...
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How to minimize surface adsorption by choice of material?
I need to do buoyancy experiments in vapours consisting of organic molecules in air using a microbalance. This involves measuring the change in weight of a sealed glass sphere when exposed to the gas. ...
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What equipment to use to make liquid oxygen?
I'd like to do some experiments with liquid oxygen but as a first step I'll have to make some. Unfortunately I don't have any experience designing cryogenic experiments. I'm thinking I'll cool gaseous ...
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How to get meniscus down to the calibration mark with a volumetric pipette
I am having trouble taking aliquots using the 10 ml volumetric pipette.
After rinsing, I draw the solution up past the calibration mark and stopper the pipette with my index finger. Then I slowly ...
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Flow cup viscometer vs rotational viscometer: limitations and use cases for each
What are the limitations of an inexpensive flow cup viscometer (or any other manual test viscometer) when compared to an expensive digital rotational viscometer?
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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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Why molten lithium burns through the glass but sodium not?
It's well-known in laboratory practice that one shouldn't melt lithium in a glass equipment and there isn't such rule about other alkali metals.
You may damage the glass with sodium but lithium will ...
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NO2 gas was detected in FTIR
We have a laser chamber full of $\ce{F2}$ gas (no air should be in the chamber) and several parts including steel, wires, ceramics, zinc.... This is for laser generation so the temperature is pretty ...
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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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Which are the appropriate washing solvents for gas chromatography equipment? [closed]
I work in a laboratory where gas chromatography is used extensively. We handle terpenes and terpenoids (alcohols, ketones, and acetates derived from terpenes), organic solvents (acetone, acetonitrile, ...
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Correct flask for reacting and distilling on hotplate?
I'm running a distillation reaction at under 100 °C with the heat coming from a hotplate (combined with magnetic stirrer). Is a Florence flask the correct vessel to use on the hotplate?
Given the ...
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Solution for storing a glass electrode
What kind of storage solution is required for a glass electrode?
Is 3 M $\ce{KCl}$ sufficient for this purpose? If so, what is the approximate pH of that solution (the solution I use presently has a ...
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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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Where can I find CAD blocks for lab glassware?
I want to draw a sketch of my apparatus for my report. I am conversant with the AutoCAD drafting software. Where can I download CAD blocks for commonly used labware items (like round bottom flask, ...
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Sodium by electrolysis through glass
In his 1926 thesis Robert Cady Burts describes the production of sodium by electrolysis of sodium nitrate through glass.
I can't find much else on this method. Are there any modern descriptions of ...
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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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How to clean glassware containing pesticide solutions
I have pesticide (dimethoate) dissolved in methanol in volumetric flasks and graduated cylinders. How do I clean this glassware properly before moving on to the next dilution of a different pesticide.
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Porous petri dish
I was wondering if there is a type of glass dish with small holes in it to use as a filter. I've found a few but they are either fritted glass disks or a type of funnel.
I was looking for something ...
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Can I get an accurate temperature reading from a flask with a built-in thermometer well?
I recently purchased a flask with a built in thermometer well, but I have discovered that simply setting a rod thermometer in the well does not produce a very accurate reading. I was wondering if ...
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How to attach a liebig condenser to a flask for reflux heating?
I know it's probably a stupid question, but I can not figure this out. I have a liebig condenser that I usually use for distillation with a Kjeldahl bulb, which makes it easy to attach to a flask ...
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Household Melting Point Standards
I'd like to accurately calibrate a digital thermometer I'm building in the range of $50^\circ$ to $120^\circ$ Celsius.
I'm aware that one can buy various chemicals that have melting points in this ...
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Stirring the reaction between hydrochloric acid and a powdered substance
For an experiment, I'm adding several substances (as powders) to hydrochloric acid, and measuring the temperature changes to calculate enthalpy. However when adding the powders, the mixture requires ...
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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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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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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 is this glassware for a distillation apparatus called?
I'm messing around with building a solar distillation apparatus, and one of the parts I think I need looks kind of like the following, except I have no idea what it is called (and thus can't look it ...
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Is the condenser for a Soxhlet extraction left open on top
My question is about the condenser used in a Soxhlet extractions. It's unusual looking compared to the rest of condensers, used in distillation for example, I've noticed it has a thin and short tube ...
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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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Devitrification vs glass transition temperature
This graph comes from a so-called "differential thermal analysis". It is studying the effects of temperature on glass.
I don't understand what the difference between "glass transition" and "...
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