Questions tagged [equipment]
Questions regarding the equipment used in labs (such as flasks, tubes etc.), their operation and maintenance.
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Cooling a 100°C beaker in cold water
In my nanoparticle synthesis, I need to cool a beaker with boiling solution (50mL beaker) rapidly to arrest a reaction at a specific size of nanoparticle. Letting the hot beaker cool passively is too ...
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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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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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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 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?
user146152
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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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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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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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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'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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