Talk:Laboratory glassware
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Request to Editors of this article
editThis is a general article which can get complicated fast.
- Please put all examples in the examples section. There were too many originally, and it made the article confusing.
- If writing about a specific piece of glassware, make sure that piece does not have its own article already.
- This is not the place to write about highly specialized lab procedures.
- Please add safety information to the article on laboratory safety. It was commented this is an encyclopedia article, not a safety guide.
Thanks! -
Major Rewrite 2017
editThese are notes from the latest rewrite describing changes.
Image Moving
editSome images were moved from the gallery to the side as detailed explanation of glassware parts.
Three images were removed from the gallery because it might be showing too much information
Deletions
editDeletion 1
editEspecially borosilicate glass, pioneered by Otto Schott, or sodalime glass are preferred glass types for scientific experiments and other work in science, especially in chemistry and biology laboratories.
- This information is too detailed and available elsewhere.
Deletion 2
editGlass use in laboratory applications is not as commonplace as it once was because of cheaper, less breakable, plasticware.
- This statement is not necissarily true for all labs.
Deletion 3
editGlass is used because it is transparent
- This is not true of acetinic glass
Deletion 4
editwhich is commonly used in reagent bottles,
- reagent bottles are one of many, many types of glassware.
Deletion 5
editLaboratory glassware may be used in certain applications because it is inert, heat-resistant, and easy to customize.
- This statement is too general and not always applicable.
- Cut examples from types of glass. There is already an example section and this can get confusing fast.
- Cut examples and cleaned up section on scientific glass blowing.
- removed tag
Deletion 6
editWhen in use, laboratory glassware is often held in place with clamps made for that purpose, which are likewise attached and held in place by stands or racks. This article covers aspects of laboratory glassware which may be common to several kinds of glassware and may briefly describe a few glassware items not covered in other articles.
- Not necissary to talk about clamps because those details are included in the article about ground glass fittings.
Deletion 7
editGlassware valves
Valves are used to redirect flows through pipes. Two types of valves used in laboratory glassware are the stopcock valve and the threaded plug valve. These and other terms used below are defined in detail since they are bound to conflict with different sources.
Stopcock valve
Stopcocks are a smooth tapered plug or rotor with a handle, which fits into a corresponding ground glass female joint. Stopcocks are often parts of laboratory glassware such as burettes, separatory funnels, Schlenk flasks, and columns used for column chromatography.
Threaded plug valve
Threaded plug valves are used significantly in air-sensitive chemistry as well as when a vessel must be closed completely as in the case of Schlenk bombs. The construction of a threaded plug valve involves a plug with a threaded cap which are made so that they fit with the threading on a corresponding piece of female glass. Screwing the plug in part-way first engages one or more O-rings, made of rubber or plastic, near the plug's base, which seals the female joint off from the outer atmosphere. Screwing the plug valve all the way in engages the plug's tip with a beveled constriction in the glass, which provides a second seal. This seal separates the region beyond the bevel and the O-rings already mentioned.
With solid plugs, a tube or area exists above and below the bevel and turning the plug controls access. In a number of cases it is convenient to fully remove a plug which can give access to the region beyond the bevel. Plugs are generally made of an inert plastic such as PTFE and are attached to a threaded sleeve in such a way that the sleeve can be turned without spinning the plug. The contact with the bevel is made by an O-ring fitted to the tip of the plug or by the plug itself. There are a few examples where the plug in made of glass. In the case of glass plugs, the joint contact is always a rubber O-ring but they are still prone to shattering.
Not all plugs are solid. Some plugs are bored with a T-junction. In these systems the plug extends beyond the threaded sleeve and is designed to form an airtight fitting with glass tubing or hosing. The shaft of the plug is bored from beyond the threaded sleeve to a T-junction just before the bevel plug contact. When the plug is fully sealed, the region beyond the bevel is separated from the plug shaft as well as the bore which leads out of its shaft. When the plug bevel contact is released, the two regions are exposed to each other. These valves have also been used as a grease-free alternative to straight bored stopcocks common to Schlenk flasks. The high symmetry and concise design of these valves has also made them popular for capping NMR tubes. Such NMR tubes can be heated without the loss of solvent thanks to the valve's gas-tight seal. NMR tubes with T-bore plugs are widely known as J. Young NMR tubes, named after the brand name of valves most commonly used for this purpose. Images of J. Young NMR tubes and a J. Young NMR tube adapter are in the gallery.
- Completely removed this section. The new section on fluid flow give an overview of this information. There are articles available on stopcock valves and threaded plug valves if this information should be merged with those articles.
Deletion 8
editFritted glass
Applications in laboratory glassware include use in fritted glass filter items, scrubbers, or spargers. Other laboratory applications of fritted glass include packing in chromatography columns and resin beds for special chemical synthesis.
- This can be moved to the article on fritted glass
Deletion 9
editFunctions
Glass has a wide variety of functions which include volumetric measuring, holding or storing chemicals or samples, mixing or preparing solutions or other mixtures, containing lab processes like chemical reactions, heating, cooling, distillation, separations including chromatography, synthesis, growing biological organisms, spectrophotometry, and containing a full or partial vacuum, and pressure, like pressure reactor.
- Verbage pulled because of the gallery and list of example glassware.
Deletion 10
editTransparency
A major advantage of laboratory glassware is assuredly the transparency of the material. It allows the chemist to supervise the progress of the chemical reaction, e.g. occurring color changes.
- This section was redundant and does not apply to acetinic glass bottles which are not transparent.
Agriculturist50 (talk) 02:54, 4 November 2017 (UTC)
Deletion 11
editCleaned up the cleaning section
Removed Bad linkages
editSuggestions for Cleaning Laboratory Glassware". Corning. Retrieved 2007-12-29.
- This link was from trade literature which is no longer posted.
J. M. McCormick (2006-06-30). "The Grasshopper's Guide to Cleaning Glassware". Truman State University.
"Glassware Safety". Univ Nevada Reno. Retrieved 2013-04-11.
- These two are dead links was from university web pages
Acetone for cleaning
edit- Acetone may be used for a final rinse of sensitive or urgently needed glassware as the solvent is miscible with water, and helps dilute and wash away remaining water from the glassware.
This is a detailed specialized procedure rarely used.
- racks these can include a hot air fan to blow the internals dry.
Details on drying racks are not needed in a general article such as this one.
Drying under a Vacuum
editAnother alternative is to place the glassware under vacuum, lower the boiling points of the remaining volatiles.
- This method is certainly possible; however, in a commercial setting a drying oven is more likely to be used than a vacuum.
Agriculturist50 (talk) 21:03, 6 November 2017 (UTC)
Transferred to different article
editA vacuum produces a pressure difference of one atmosphere, approximately 14 psi, over the surface of the glass. The energy contained within an implosion is defined by the pressure difference and the volume evacuated. Flask volumes can change by orders of magnitude between experiments. Whenever working with liter sized or larger flasks, chemists should consider using a safety screen or the sash of a flow hood to protect them from shards of glass, should an implosion occur. Glassware can also be wrapped with spirals of tape to catch shards, or wrapped with webbed mesh more commonly seen on scuba cylinders.
Glass under vacuum becomes more sensitive to chips and scratches in its surface, as these form strain accumulation points, so older glass is best avoided if possible. Impacts to the glass and thermally induced stresses are also concerns under vacuum. Round bottom flasks more effectively spread the stress across their surfaces, and are therefore safer when working under vacuum.
- This material was transferred to the article on bell jar
Legacy Discussions prior to 2017
edit2005
editOr maybe "semantic precision concerns". These are all really minor issues, but they need to be addressed by somebody who's more familiar with lab jargon than I am.
- Many of the items mentioned are often made from quartz or plastic, not glass. That doesn't necessarily mean you can't call them "glassware" -- usage is more important than etymology. But do lab workers typically refer to, say, a plastic test tube as "glassware"?
- "Tools" is vague and misleading. But what's a better word? Containers?
- "Used by chemists and biologists in performing scientific experiments" seems to leave out a lot. Do other kinds of scientists never use glassware? What about non-scientists working in a laboratory? Non-experimental lab procedures?
---Isaac R 16:08, 27 Apr 2005 (UTC)
- I took off the disputed tag; that's really for situations where people are involved in a heated argument over the material and it can't easily be resolved. I don't think that's the case here (at least not yet...)
- Rather than try to pick the right few words, I expanded on lab glassware and what it's for. Hopefully this will explain the idea to someone who comes by.
- As for your specific points, they're a bit tricky. I don't know if people call a plastic test tube "glassware". I think (not that I work in a lab) that people say "glassware" when they're speaking generically (even if all the glassware is made of plastic) but when speaking about something as specific as a test tube they'd be more specific about what it is ("test tube") and what it's made of "plastic").
- Of course they're not just used by scientists, and not even just for scientific experiments; hospitals use them, people drink out of beakers, bell jars make great display cases, and so on. But this an encyclopedia, after all, not a dictionary, and so our goal should be to explain what it is, where it comes from, why it's made of glass, when people started using glass, and so on. --Andrew 16:35, Apr 27, 2005 (UTC)
2009
editok so were talking too much about the methods of using and cleaning glassware, but not about the glassware itself. Admin please look at this article. 71.186.24.251 (talk) 06:17, 24 January 2009 (UTC)
- Please read the article again. Most of the article is about features common to many types of glassware. There is a small section on cleaning and almost nothing on method of use beyond what is necessary to explain the construction of the discussed features. Please be more specific with your concerns if you still have any.--OMCV (talk) 06:40, 24 January 2009 (UTC)
2010
editI think that's getting a little overly picky. The only remaining group of scientists is physicists, and they don't often use the kind of glassware discussed here. As to the plastic point, it's a fair question, but that equipment will usually all be in the same cupboards as the glass anyway. We could rename the article 'scientific equipment', but then it be a large book as opposed to an article. Or we could create an article specifically for plastic lab ware, then we'd have redundancy. Clumping them together as glassware (or labware) seems the best of both and is how it's done in real labs. —Preceding unsigned comment added by 82.24.47.178 (talk • contribs) 17:00, 2 July 2010 (UTC)
Under 'Service Temperatures', in the line "Borosilicate anneals at 560 °C (1,040 °F), this removes built in stain in the glass." should the word 'stain' perhaps be 'strain'? 75.42.91.166 (talk) 21:19, 8 August 2010 (UTC)
MERGERS & DISAMBIGUATION
editI was trolling around glassware this afternoon and noticed some serious redundancy between articles. In particular, the ground glass joint article is virtually identical to sections in laboratory glassware. Also, those joints appear no where other than on laboratory glassware, so the two should be merged.
Another concern is that searching 'glassware' doesn't bring up a disambiguation page. It would be better to rename it 'glassware' and have the menu come up when people search for it, which is what I expect most people will use as a search term.
I have also seen numerous articles on different glassware forms. Could we not have a section on the page with all the common forms listed with a simple statement next to each? I realize this will extend the page a fair amount, but it also seems the most sensible in terms of what people would be coming to the glassware article for. If they don't know the name or use of a piece of glass, they're not going to know to search for it in the first place. If you look at things like the round bottom flask article, a lot of that could be said about all the other forms of flask, tube, column, bend, head or beaker. —Preceding unsigned comment added by 82.24.47.178 (talk • contribs) 17:00, 2 July 2010 (UTC)
"Reagent Bottle" Entry Created - Please Add!
editI just created the entry for Reagent bottle. If you have more useful and knowledgeable information, please do add it. Radical Mallard (talk) 16:54, 6 July 2010 (UTC)
2011
editWhat does this mean?
editWhat does this: "As most vacuum chemistry occurs with at least 90% of the atmosphere removed, the pressure difference is often negligible between laboratories; a typical diaphragm pump, aspirator or rotary vane pump will remove this level of atmosphere." mean? Especially the "negligible between laboratories" bit. 213.122.50.24 (talk) 23:52, 2 February 2011 (UTC)
Other Discussion
edit[I'm not sure if I'm adding this comment acceptably, so please bare with me]I am a glass blower who makes both lab ware and 'smoking glass', and I must say that the glass ground joint page absolutely deserves it's own space/page. Ground joints are increasingly so no longer just for labs, they are completely evolving smoking paraphernalia. Trying to merge this glass ground joint page with a labware only section would be nearly as erroneous as doing the same for rubber grommets, scientific research is merely one application for them. If anything, they should have their own page, which the science sections would link to.- Hope that makes sense, (Aqueforyou (talk) 18:19, 26 April 2011 (UTC))
2012
editThere is confusion between laboratory glassware and laboratory plasticware. This line was removed because a polyethylene container is clearly plasticware. Special-purpose materials are also used; for example, hydrofluoric acid is stored and used in polyethylene containers because it reacts with glass.[1]
Perhaps a laboratory plasticware article may be in order. There is probably just as much plasticware as there is glassware available on the market. I'd let glassware be its own article, because not all information, e.g. ground fittings, would not be applicable to plasticware. Plasticware would include clamps and other materials that could not be made of glass.
References
- ^ "Hydrofluoric acid MSDS". J. T. Baker. Retrieved 2007-12-29.
Cleaning Laboratory Glassware - Acetone
editIt is stated in this section that water forms an azeotrope with acetone, however on the page https://en.wikipedia.org/wiki/Azeotrope_%28data%29, it is stated that acetone does not form any azeotrope with water, with two citations. — Preceding unsigned comment added by 89.100.118.241 (talk) 23:30, 17 February 2012 (UTC)
2013
editIs Quartz considered Glassware?
editWhether or not quartz is lab glassware is tricky because both are silicone dioxide; however, quartz is crystal and glass is amorphous. 22:30, 8 March 2013 (UTC)
I guess quartz would have to be a type of glassware. Vycor is a trade brand of glass that is almost quartz, which has exceptionally high thermal properties over silicate. Jhmartinii (talk) 22:18, 11 March 2013 (UTC)
Quartzware is a term used by some laboratories. Agriculturist50 (talk) 18:49, 21 November 2017 (UTC)
Deletions and Material Transferred to Other Articles
editThis is a broad topic, it is necessary to subdivide to make this article readable.
Borosilicate Glass
editThis material was removed because it is covered on the article on borosillicate glass.
500 °C (932 °F) is the maximum service temperature for borosilicate glass as, at 510 °C (950 °F), thermal strain begins to appear in the structures. Operation at this temperature should be avoided and only intermittent. Bear in mind that glassware under vacuum will also have around one atmosphere of pressure on its surface before heating and so will be more likely to fracture as temperature transitions increase. Vacuum operation should be used if the atmospheric temperatures required are above a few hundred degrees Celsius, as this often has a dramatic effect on boiling points; significantly lowering them.
560 °C (1,040 °F) is the temperature borosilicate glass anneals at, this removes built in strain in the glass.
820 °C (1,510 °F) is the temperature borosilicate glass softens and is likely to deform. [citation needed] and at 1,215 °C (2,219 °F) it becomes workable. was removed because it is under the article on borosilicate glass. Jhmartinii (talk) 14:54, 11 March 2013 (UTC)
Fritted Glass
editThe material on fritted glass was moved to its own article.
Jhmartinii (talk) 17:56, 11 March 2013 (UTC)
Glass Connectors
editThis material was already in the article on glass connectors. This is too detailed for the laboratory glassware article.
Connectors may be made from a variety of materials. Ground glass joints composed of all glass quickly and easily fit leak-tight apparatus together from commonly available parts. For example, a round bottom flask, Liebig condenser, and oil bubbler with ground glass joints may be rapidly fitted together to reflux a reaction mixture. This is a large improvement compared with older methods of custom-made glassware, which could be time-consuming, expensive, or used less chemical resistant and heat resistant corks or rubber bungs and glass tubes as joints. Jhmartinii (talk) 19:32, 14 March 2013 (UTC)
Cleaning Procedures
editRemoved cleaning be hydro-fluric acid because this is a very dangerous and highly specialized procedure. Probably not suitable for a general article. Jhmartinii (talk) 18:25, 11 March 2013 (UTC)
Chromic acid is not a preferred method if the glassware is to be used for the biological sciences, as chromate ions can implant themselves in the glass and produce anomalous results when it is subsequently used for cell cultures; to which the ions are toxic. A proprietary alternative known as NoChromix is available, which is essentially a sachet of largely ammonium persulfate and a smaller amount of surfactant. This is poured into a bottle of concentrated sulfuric. Like concentrated hydrogen peroxide, ammonium and sodium persulfate are strong oxidisers, yet they are not hydroscopic and are more stable. This allows them to be more easily stored and used. When mixed with concentrated sulfuric, they begin releasing oxygen, which can oxidise the carbonaceous dehydration products formed from organic residues by the sulfuric to carbon dioxide; 'burning' them off the glass. The rate of effervescence is slower than that of strong piranha solution, allowing more time for deposits to mechanically break up and for the mixture to be used before fully decomposing. This same method is used in some PCB etching tanks, where sodium persulfate (fine etch crystals) are combined with sulfuric acid to oxidise the copper surface and then make it water soluble as its sulfate. {Citation needed|date=May 2011}
Too Much Information.... added ... and perhaps more suitable proprietary solutions may be used to clean organics. Jhmartinii (talk) 18:31, 11 March 2013 (UTC)
Removed drastic cleaning procedures because they are unusual, highly specialized, and a potential hazard. These methods are so specialized and not suitable for description in a general article.
Drastic methods, generally considered unsafe for routine use because of possible explosions and the corrosive/toxic materials involved, of cleaning glassware exists. More specialized literature should be consulted before attempting these methods. These methods include:
- A saturated solution of sodium or potassium hydroxide in an alcohol ("base bath"),followed by a dilute solution of hydrochloric acid ("acid bath") to neutralize the excess base. Strong bases, such as sodium hydroxide, cleans glass by dissolving a tiny layer of silica[citation needed], to give soluble silicates. Care should be taken using strongly alkaline solutions to clean fritted glassware, as this will degrade the frit over time.
- Aqua regia is good for removing metals from fritted glass.
- Piranha solution, chromic acid, and perhaps more suitable proprietary solutions can be used to remove organics.
Jhmartinii (talk) 19:39, 14 March 2013 (UTC)
Material Related to Hotplates
editIn a student laboratory, baths can be hazards if they spill, overheat or ignite, because they have a high thermal inertia (meaning they take a long time to cool down) and mantles can be very expensive and are designed for specific flask volumes. Two alternative methods for heating glassware can be used instead. One method is to suspend glassware slightly above the surface of the plate with no direct contact. This not only reduces the temperature of the glass, but it slows down the rate of heat exchange and encourages even heating. This works well for low boiling point operations or when a heat source's minimum temperature is high. Another method, called a teepee setup because it looks a little like a tipi, is to suspend glassware above a plate and surround the flask by a skirt of tinfoil. The skirt should start at the neck of the flask and drape down to the surface of the plate, not touching the sides of the flask, but covering the majority of the plates surface. This method is for glassware to be heated at higher temperatures because the flask is warmed indirectly by the hot air collecting under the skirt and unlike simply suspending the glassware, this method is better protected from drafts. Both these methods are useful in a student laboratory as they are cheaper, effective, safe, and the user does not have to wait for a bath to cool down after use.
to the article on hotplates. This is way to detailed for a general article on glassware.
Jhmartinii (talk) 14:18, 11 April 2013 (UTC)
Unknown and Unsigned
editAccuracy issues
editAll these sources suck and give a 404 errror.
2017
editThis information was cleaned up and rearranged chronologically as best as possible Agriculturist50 (talk) 20:23, 6 November 2017 (UTC)
Gallery
editThe gallery was removed because Wikimedia commons categories have been reorganized. (This gallery has the potential to get large quick.)
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A glass desiccator
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Test tubes containing a liquid sample.
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A Büchner funnel with a sintered glass disc
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A glass retort
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An apparatus using a coil condenser.
==Wiki Education assignment: History of Science== This article was the subject of a Wiki Education Foundation-supported course assignment, between 18 January 2022 and 13 May 2022. Further details are available on the course page. Student editor(s): MaxD02, DaleHabe (article contribs). Peer reviewers: MitchB323, Sweiler99, Wyattsnyder, Chasew2000, Tim Baltmore, Eschell20, Ankithj.
Rewrite for project
editHistory section was lacking and disorganized, so I am adding more information to history section and reorganizing it.--MaxD02 (talk) 15:38, 8 April 2022 (UTC)
I am going to add a more detailed definition of borosilicate glass and polytetrafluoroethylene. DaleHabe (talk) 16:57, 8 April 2022 (UTC)