Skip to main content

Questions tagged [equipment]

Questions regarding the equipment used in labs (such as flasks, tubes etc.), their operation and maintenance.

51 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
5 votes
0 answers
269 views

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% ...
Necoras's user avatar
  • 151
4 votes
0 answers
82 views

An unknown glassware piece from our cupboard

We have multiple of these. It is a small glass funnel with splits into 3 spouts from it. Now, we are thinking it might be similar to a cow receiver, however, I have never seen one this small or ...
hreeve1's user avatar
  • 99
4 votes
0 answers
39 views

Unknown possibly handmade glassware- description in information below

Okay, Another random item from the cupboard (unknown users or discipline of life sciences unknown) could be anything up to 40 years old.... This appears to be a 2 neck quickfit adapter (B19 and B14) ...
hreeve1's user avatar
  • 99
4 votes
0 answers
188 views

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. ...
Dirk Bruere's user avatar
  • 1,672
3 votes
0 answers
734 views

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?...
Max Power's user avatar
  • 207
3 votes
0 answers
395 views

What might be the reason for the longer stem found in some separation funnels?

Most separation funnels have a stem around 50 to 70 mm long (often less if fitted with a ground taper joint) that is used to direct the output into a receiving flask. While the stop-cock has a ...
KalleMP's user avatar
  • 646
3 votes
0 answers
185 views

What is this "bulbous"/"blood sugar" test tube used for?

I was at an antique and bric-a-brac store, and I found several pieces of glassware. They were pretty cheap, so I purchased some of the more interesting ones. Among them were a few somewhat strange "...
ChemBird's user avatar
  • 512
3 votes
0 answers
275 views

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.
Mickhael Jay's user avatar
2 votes
0 answers
39 views

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 ...
Thomas's user avatar
  • 31
2 votes
0 answers
92 views

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 ...
Hugosh's user avatar
  • 41
2 votes
0 answers
52 views

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. ...
Jason C's user avatar
  • 1,172
2 votes
0 answers
94 views

Appropriate ways to remove aluminum from the surface of glass?

I'm looking for a way to treat the surface of borosilicate glassware such that it won't contaminate solutions of puriss reagents in conditions that pure $\ce{SiO2}$ wouldn't, yet keep the bulk ...
Hans's user avatar
  • 1,097
2 votes
0 answers
122 views

Does mercury react with polycarbonate?

Looking around at various material compatibility charts, they seem quite divided on the compatibility of metallic mercury and polycarbonate. Some sources (here, here, or here) indicate that ...
loudaslife's user avatar
2 votes
0 answers
128 views

What has happened with the pH-meter?

The glass sensor has became red inside like something melted. I stored it in a liquid with pH that mentioned in the manual. What is that and why could that happen, how often that happens with pH-...
R S's user avatar
  • 315
2 votes
0 answers
230 views

NaOH vs Polypropylene

This source lists polypropylene as suitable for use with NaOH. However, this paper seems to demonstrate that NaOH slowly degrades polypropylene (even at fairly moderate temperatures). Does anyone ...
Hans's user avatar
  • 1,097
2 votes
0 answers
60 views

Is it possible to fractionally distill a compound made up of substances with very similar boiling points?

Let's say I have a solution that is made up of substances that have very similar boiling points, say less than 5 degrees apart. Is it even possible to fractionally distill those substances, say, using ...
user379468's user avatar
2 votes
0 answers
659 views

Does this wire gauze contain asbestos? Can I tell visually?

I bought a wire gauze which claimed to be made of ceramic, and asbestos-free. However, I bought it from Amazon (not a trustworthy source), and I see fibers around the edge of the center. Is there a ...
piojo's user avatar
  • 337
2 votes
0 answers
237 views

Alternative to mercury bubbler for increasing boiling temp?

A common reaction for forming the octachlorodirhenate(III) anion is to heat tert-n-butylammonium perrhenate in benzoyl chloride at 209 ºC. If you look up the info for benzoyl chloride, one sees that ...
Dustin Wheeler's user avatar
2 votes
0 answers
153 views

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?
Anand's user avatar
  • 121
2 votes
0 answers
474 views

Glassware Test Instruments CAD blocks library

I am designing a fairly simple distillation for dichloromethane. Being an engineer I feel more comfortable working with precise dimensions of both the separate glass vessels (condensers, evaporators, ...
Ivan P.'s user avatar
  • 211
1 vote
0 answers
64 views

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 ...
Ronith's user avatar
  • 1,343
1 vote
0 answers
46 views

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{...
Steve Dutky's user avatar
1 vote
0 answers
337 views

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(\...
gagagaga's user avatar
1 vote
0 answers
50 views

HDPE vs PP for storing pure aldehydes

I know both HDPE and PP have at least some degree of resistance to aldehydes, esters and aliphatic hydrocarbons. I am concerned however about minute contamination over time of pure samples and so I ...
Hans's user avatar
  • 1,097
1 vote
0 answers
73 views

Is the width of a Soxhlet Condenser Inherent to its Function?

Soxhlet extractors are often coupled to a specifically designed condenser with a very large lower joint. Is this inherent to it's function as a condenser in the apparatus or only because the Soxhlet ...
Hans's user avatar
  • 1,097
1 vote
0 answers
74 views

Mercury bulb on spirit thermometer?

I recently broke a Quickfit distillation thermometer and the bulb had liquid metal in it. I assumed it's mercury and acted accordingly. However, the column looks like spirit filled (blue liquid). Has ...
Vlad's user avatar
  • 1,021
1 vote
0 answers
49 views

Reason for rounded fitting at the top end of Allihn Condenser

I am purchasing an essential oil distillation setup. The Allihn Condenser at the top end, and the attached glassware, are rounded. It is supposedly 24/40. I have never seen this. If one of them broke, ...
Sofia's user avatar
  • 11
1 vote
0 answers
82 views

Permanent storage container with electrode for electroplating

I'm not a chemist at all but I am looking for a specific type of container which I'm sure must exist but I don't know it's name. We want to store non-toxic (non-cyanide) gold solution for ...
Metioche's user avatar
1 vote
0 answers
154 views

Can we use potassium iodide as pH meter electrode storage solution.? If not then why?

If KCl is not available can KI be used to store pH probe meters? Both are potassium salts.
Husnain Yousaf's user avatar
1 vote
0 answers
380 views

How does the "sample type" selection on the MassHunter software for Agilent 7900 ICP-MS affect the quantitative results?

I'm new to using the instrument, and recently I have tried to measure Cr in both the eluent(1% nitric acid) and a method blank (also 1% nitric acid, but after it has gone through the entire analytical ...
Waif's user avatar
  • 126
1 vote
0 answers
35 views

What is the most simple way to cut through a steel with very thin aluminum coating to obtain cross section without damaging the coating?

I needed to take cross section characterization of an aluminum coating. I tried to use a hand saw to cut through it, but it destroys the coating, and usually is separated with the substrate as I ...
Acid's user avatar
  • 537
1 vote
0 answers
283 views

What is substance that has high melting point in its powder form?

In laminated glass bending process 2 glass sheet will be superposed in a furnance.The seperation powder will be interposed between layer for avoid 2 glass sheet being bound together. I'm trying to ...
Ko Go's user avatar
  • 19
1 vote
0 answers
93 views

What kind of glass glue can replace silicone?

I tried to put the 'Ferrofluid' and the clear liquid in a large glass tank. My glass tank was bonded with silicone. However, silicon reacted with 'Ferrofluid' ('Ferrofluid' became sticky and hardened)....
닥드정's user avatar
1 vote
0 answers
470 views

Possible Method for Testing Ammonia (and Nitrite/Nitrate) Concentration in Water

I am designing an automated system testing device for my high school's aquaponics club. We need to test for a number of ion concentrations, including ammonia and nitrite/nitrate. In my research, the ...
e6r339b's user avatar
  • 11
1 vote
0 answers
51 views

Automated chemistry test machines? What is currently done, and what is research leaning towards?

There are small and large chips and machines to effect admixtures,blends, fusions of different chemicals into a variety of test samples, and there are machines to measure many vials of all kinds of ...
bandybabboon's user avatar
1 vote
0 answers
151 views

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 ...
RothX's user avatar
  • 111
1 vote
0 answers
324 views

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 ...
GilAlexander's user avatar
1 vote
1 answer
902 views

Condensation of Ethylene Glycol

I'm looking to reflux a 250 mL of ethylene glycol solution. Would an Allihn condenser be suitable; if so what length?
Jeremy Vandenberg's user avatar
0 votes
0 answers
74 views

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 ...
Troy Peterson's user avatar
0 votes
0 answers
84 views

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 ...
user642965's user avatar
0 votes
0 answers
48 views

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 ...
And's user avatar
  • 238
0 votes
0 answers
691 views

What is the product of ammonia reacting with silicone?

I used a soft silicone hose to carry ammonia at ~70 °C. I was surprised to later find the hose had hardened. A quick materials compatibility search for silicone had given me a lot of info but an "...
Hans's user avatar
  • 1,097
0 votes
0 answers
28 views

Affordable, non-contaminating flexible tubing for common acids

Which tubing material is affordable, flexible, widely available, and suited for transporting very pure acids ("puriss." products) in their most concentrated form without contaminating them? ...
Hans's user avatar
  • 1,097
0 votes
0 answers
40 views

Compact way to regulate 3000psi (200bar) down to 30psi (2bar)?

This was originally posted on the Lego page, and closed because it's not actually about Lego itself. I thought I'd give them a chance first, in case someone had done this already and had some ...
AaronD's user avatar
  • 149
0 votes
0 answers
393 views

Looking for advice regarding a larger scale soxhlet extraction

I have successfully completed a few soxhlet extractions at a much smaller scale using a soxhlet extractor with ~200ml capacity. With that, I was able to extract from ~100g of pre-powdered, sonicated ...
Joe Black's user avatar
0 votes
0 answers
83 views

BOD5 respirometric method

I operate in a wastewater treatment plant laboratory and I use respirometric method for BOD5 measurement (hach direct plus). Recently I am obtaining high value for BOD (biological oxygen demand) for ...
Shafik Saad's user avatar
0 votes
0 answers
774 views

Highly concentrated NaOH solution at high temperature vs borosilicate glassware and cellulose?

I've read here on stack-exchange that NaOH will react with glass through the following reaction: 4 NaOH + SiO2 ⤑ Na4SiO4 + 2 H2O I would like to briefly heat a highly concentrated NaOH solution to ...
Hans's user avatar
  • 1,097
0 votes
0 answers
62 views

Unknown glassware please help, vshaped with a small bulb on one side, hollow but narrow to both sides!

Looking to try an identify some glassware we have found in a cupboard. This is just the start of it... 1 item here, v-shaped, small bulb but hollow, narrow entrance and exit...
hreeve1's user avatar
  • 99
0 votes
0 answers
1k views

Can Pyrex laboratory grade glassware be heated on a stovetop?

I don't have access to a hot plate, I was wondering if Pyrex glass can be safely heated on a stove top. It isn't an open flame, it's a radiant stove top with an electric coil underneath a smooth ...
Aeolus's user avatar
  • 405
0 votes
0 answers
81 views

Wetting properties of FTO coated glass

I am trying to spin coat a layer of polymer+Quantum Dots on an FTO coated glass slide. My material is forming agglomerates at the edges of my slide. My polymer is PVK which has a conc of$\approx 4.5mg/...
Ghosal_C's user avatar
  • 501