Glassware is plentiful in laboratories and comes in various shapes and sizes. It has become more common to replace glass vessels with less expensive, more robust, and less fragile plastics nowadays. But some chemicals, experiments, or applications still require glassware.

There are numerous explanations for this. To begin with, glass is relatively inert, which means it will not react with the chemicals or substances placed inside, therein not tampering the results. It’s also transparent or translucent, making it easier to monitor and heat-resistant to withstand extreme temperatures. It is straightforward to shape and can be mould into any desired shape.

Beakers, Petri dishes, vials, burettes, and cylinders, among other glassware, are always present even in the most miniature laboratory. This is due to its unusual inert properties, which allow chemical molecules to be inserted within it. But not all glasses are created equal. Different materials, such as quartz, soda-lime, borosilicate, and actinic, are utilised to make laboratory glass.

Glass has the following general characteristics:

Glass outperforms plastic in various chemical environments, including acids, alkalis, organic solvents, saline solutions, and water. Hydrofluoric acid, powerful alkalis used at high temperatures, and concentrated phosphoric acid are the only substances that can break glass.

Glass has additional advantages in the lab, such as dimensional stability and transparency, even at high temperatures. Other benefits include the availability of many sizes of scientific equipment and the ease with which glass may be cleaned. Pyrex, a type of glass, is heat resistant and ideal for reagent and chemical storage.

Tips for dealing with laboratory glass:

• When working with glass in the laboratory, it’s crucial to keep its mechanical and thermal shock restrictions in mind. Make sure you follow all safety precautions at all times. Make sure you stir and cool an exothermic reaction, such as dilute sulfuric acid, and that the response is in a suitable vessel.
• Exothermic processes should not be performed in graduated cylinders or volumetric flasks. If you use heating plates to heat volumetric instruments, you risk breaking them.
• Glass instruments should not be exposed to extreme temperature or pressure changes. Allow no air to enter evacuated glass apparatus quickly, and never evacuate containers with flat bottoms. They’re not meant to be used in a vacuum. On empty glass instruments, apply effort (not force) steadily and in a regulated manner. Protect yourself with goggles, gloves, and screens.

Here are some of the more common laboratory glass types:

Soft Glass:

Soft glasses are physically more delicate than others. Furthermore, these glasses preserve their soft working qualities throughout a more comprehensive temperature range. Soda-lime glass is the most prevalent variety of smooth glass. The soda-lime glass is made up of sodium carbonate (Na2O) and calcium oxide (CaO) or magnesium oxide (MgO). It is the least expensive variety of glass to create laboratory glassware due to its lower energy consumption (lower melting temperatures) and longer working hours. The proportions of a soft glass’s constituent elements determine its quality. The smooth glass is often made with 8 per cent to 12 per cent lime (by weight) and 12 per cent to 17 per cent soda (by weight). Devitrification can occur during the production process if the lime content is too high. On the other side, a low lime concentration might cause natural weathering and water attacks on the glass. The soft glass includes sodium silicate and lead glass, and soda-lime glass.

The major problem of utilising soft glass for laboratory glassware is that any device produced with these types of glass is virtually unrepairable. Furthermore, because the thermal coefficients of expansion of smooth glass are relatively large, it is prone to shatter when the flame of a gas-oxygen torch meets it.

Quartz Glass:

In the laboratory, high-temperature and UV-transmission glasses are referred to as “quartz.” Quartz glass is often used in laboratories due to its excellent thermal and UV transmission properties. Unlike other glasses that shrink and melt at temperatures beyond 1200°C, Quartz glass retains its solid shape. Furthermore, it can sustain thermal shock that would likely shatter all other glassware due to its exceptionally low thermal coefficient of expansion (about 5.0 x 10′′7 Acm/cm/°C). Quartz glass transmits the most extensive spectrum of light frequencies compared to different glass kinds.

Hard glass:

The ability of hard glass to endure an abrasion impact three times that of the soft glass has earned it the term “hard.” It also sits at a greater temperature and “hardens” more quickly. Hard glass can sustain far greater thermal shocks than soft glass because of its lower thermal coefficients of expansion. Furthermore, alkaline solutions and various other chemicals are chemically resistant to hard glasses. The most prevalent type of hard glass is borosilicate glass.

Laboratory Materials made of Glass:

Flasks:

To prepare standard solutions or weigh for density calibrations, volumetric flasks measure accurate volumes of liquids. Volumetric flasks aid quantitative laboratory work. A volumetric flask is made of chemically resistant borosilicate with a low expansion coefficient for the best combination of resistance and readability. Volumetric flasks can be capped to prevent material from evaporating and maintain the material’s purity.

Beakers:

A beaker is a cylindrical glass vessel used to hold liquids, store them, mix them, and transport them. The glass beaker is a versatile laboratory tool that can perform chemical reactions, measure liquids, heat solutions over a Bunsen burner flame or collect them in a titration experiment. The beakers’ uniform wall thickness makes them excellent for heating applications, and they include a big labelling field for convenient labelling. Increased glass content provides more excellent mechanical stability to the beakers. The strengthened rim decreases the chance of fracture and boosts shock resistance.

Glass Bottles:

Handlers benefit from the glass bottles’ exceptional mechanical robustness, protecting them from breaking or cracking. They have a wide and varied set of applications. The bottles make handling samples, identifying them, and using them more accessible. Additionally, the bottles and accessories make laboratory work more comfortable, safer, and cost-effective. The availability of a wide variety of laboratory bottles allows researchers to conduct various research experiments in them.

Pipettes:

A pipette is a laboratory tool used to transmit a measured volume of liquid, generally as a media dispenser, in chemistry, biology, and medicine. Pipettes are available in various designs and levels of accuracy and precision, ranging from simple single-piece glass pipettes to more complex adjustable or electronic pipettes. Many pipettes establish a partial vacuum above the liquid-holding chamber and then selectively release that vacuum to draw liquid up and out. The precision of measurements varies substantially depending on the equipment.

Glass Rods:

Glass rods, also known as stirring rods, stair rods, or solid glass rods, are made of borosilicate glass and quartz. Its diameter and length can be tailored to your specifications. Glass rods can be classified into two types based on their diameters: laboratory stirring rods and sight glass rods. Glass rods are resistant to corrosion. It is acid and alkali resistant. It has high toughness and can work in temperatures as high as 1200°C for an extended period. The stirring rod is commonly used in laboratories and industries because of these characteristics. A moving glass can be used in the laboratory to speed up the mixing of chemicals and liquids. It can also be used to research. Glass rods are used to make gauge glass in the industry.

Glass Thermometers:

The fluid/glass thermometer is the most widely used thermometer for measuring temperatures worldwide. It comprises a reservoir coupled to a sealed glass tube with a small internal diameter (like a lumen). The fluid in the pool and tube expands and pushes up as the temperature rises. The temperature is shown via a scale on the box and the location of the expanded fluid.

Watch glass:

A watch glass is a spherical piece of glass used in laboratories to evaporate liquids, weigh solids, heat substances or powders, and cover beakers to prevent dust or other particles from entering the beaker. Remember that the watch glass does not entirely seal the beaker. Thus, gas exchanges will still happen. When used as an evaporation glass plate, the watch glass provides a clear, direct view of crystallisation and can be set on a contrasting colour background to improve visibility.

Conclusion:

Almost every piece of lab equipment has a specific function. You must, however, look after them. If you want your laboratory equipment to last longer, maintain it properly. It would help if you never scrub with a wire brush since it can cause rust.

References:

https://www.scientificglassservices.co.uk/types-of-laboratory-glassware-and-their-uses/

https://www.nextdayscience.com/blog/everything-about-glassware-lab.htm

https://www.thoughtco.com/chemistry-glassware-names-and-uses-606047

https://www.westlab.com/blog/2018/11/19/the-different-types-of-glass-in-the-lab

https://www.jove.com/v/10161/common-lab-glassware-and-uses