The Erlenmeyer flask is a staple scientific glassware and one of the world's most recognizable pieces of scientific equipment. Whether you're growing a cell culture or performing a titration, the Erlenmeyer flask serves many different purposes and is helpful to people in a range of scientific settings.

But what is the Erlenmeyer flask, and, more importantly, how does it work? In this guide, we'll teach you everything you need to know about this iconic flask, including how they work, what they are used for, and how to get the most out of them when performing your own experiments.

What is an Erlenmeyer Flask?

The Erlenmeyer flask is a piece of laboratory glassware used to measure, mix, transport, store, cool, and boil liquids. The flask is commonly used for titrations because of its unique conical shape, allowing easy mixing and simple storage. In addition, Erlenmeyer flasks' narrow necks make them ideal for stirring solutions without risk of spillage.

Erlenmeyer flasks are noted for their versatility, durability, and resistance to temperature change, making them a perfect addition to almost all laboratory settings.

The flask is named after the German chemist Emil Erlenmeyer, the first man to invent the design in the late 19th century.

Is there a difference between an Erlenmeyer, conical, and titration flask?

You may be surprised to learn that there is no difference between conical flasks, titration flasks, and Erlenmeyer flasks. The terms are used entirely interchangeably, and all mean the same thing.

The term 'conical flask' is most commonly used in British English, while 'Erlenmeyer flask' and 'titration flask' are used in the US.

How is an Erlenmeyer flask designed?

Erlenmeyer flasks are distinguished by their conical body, flat bottom, and narrow neck that widens at the top.

The unique design of the Erlenmeyer flasks enables easy pouring, swirling, and mixing. The thin cylindrical neck allows the flask to be easily sealed with a bung or rubber stopper. Many flasks are also equipped with vented closures, allowing gasses to escape that could cause pressure to build up while boiling liquids or fermenting cultures.

Most Erlenmeyer flasks have measurement markings on the side, indicating the volume of liquid in the flask. The flask can have any number of markings, though most have a line every 25-50ml. Some bigger flasks that store large amounts of liquid may only have a marking every 100-200ml.

What are Erlenmeyer flasks made of?

The Erlenmeyer flask is typically made from borosilicate glass, a durable material boasting excellent chemical corrosion and thermal shock resistance. This tough glass allows the Erlenmeyer flask to withstand rapid temperature changes, making it ideal for various types of laboratory experiments.

Plastic Erlenmeyer flasks (like this one) are also readily available in materials such as polypropylene. This strong, lightweight plastic is more resistant to temperature change and won't shatter, making it useful for experiments requiring greater heat or corrosion resistance.

That said, some chemicals may react poorly with plastic flasks, affecting a researcher's ability to take accurate measurements. For this reason, borosilicate glass flasks are still the most popular choice for everyday experiments. It's essential to check the specific requirements of your experiment to gauge which flask is best suited to your needs.

What sizes are available?

Erlenmeyer flasks are available in many different sizes, making the flask suitable for a broad range of scientific applications. The most common flask sizes used in scientific studies are 25ml, 50ml, 100ml, 250ml, 500ml, and 1000ml.

Some large Erlenmeyer flasks may even go up to 2000ml or 5000ml. These are usually reserved for industrial purposes and aren't typically suited to a standard laboratory.

When choosing the correct flask size, it's important to consider both how much volume is required for the application and how much space is required to shake vigorously should it be required. In most circumstances, it's best to choose a flask larger than the amount of liquid it will hold to allow for effective stirring and prevent spillage.

Erlenmeyer flasks and beakers: what's the difference?

Both beakers and Erlenmeyer flasks have their place in the laboratory, but the key differences between the two glassware styles mean each is suited to a different function.

The main difference between Erlenmeyer flasks and beakers is the shape. While the Erlenmeyer flask is known for its conical shape, the beaker is cylindrical with flat sides. A beaker also has a spout at the top to allow for easy pouring of liquids, whereas an Erlenmeyer flask does not.

Beakers are normally used for measuring, decanting, and transporting liquids. The larger size and pouring spout make it well-suited to this purpose.

In contrast, the Erlenmeyer flask is more commonly used for mixing and reacting, as the conical shape allows for easy and vigorous stirring. Erlenmeyer flasks are also built to withstand more heat than a standard beaker, making them ideal for exothermic reactions.

Erlenmeyer flask and volumetric flasks: What's the difference?

Although the volumetric flask and Erlenmeyer flask are both excellent additions to any lab setting, they each have distinct characteristics that make them more suited to specific applications.

Volumetric flasks are pear-shaped, with a taller, narrower neck than Erlenmeyer flasks. They are typically only made to measure one volume accurately, whereas an Erlenmeyer flask is often graduated with several markings.

Erlenmeyer flasks are considerably less precise than volumetric flasks. The volumetric flask is calibrated to a high degree of accuracy, typically to the nearest 0.05ml (for class A flasks). In contrast, many Erlenmeyer flasks are only calibrated to the nearest 5%.

This means that a 100ml measurement on a class A volumetric flask will always fall within the range of 99.95ml-100.05ml. In contrast, an Erlenmeyer flask calibrated to 100ml could fall anywhere between 95ml and 105ml.

This makes volumetric flasks the ideal glassware for scientific applications that require a high degree of accuracy, such as preparing standard solutions or liquids that need to be formulated to a precise concentration.

That said, the Erlenmeyer flask is better suited to experiments that require heating or boiling, as volumetric flasks are not suited to rapid temperature changes.

What is an Erlenmeyer Flask used for?

The unique shape and resistant qualities of the Erlenmeyer flask make it the perfect piece of lab equipment for everyday experiments. It serves various purposes for chemists, physicists, and biologists alike. Let's look at some of the primary uses for the flask in scientific applications.

• Mixing chemical solutions: The Erlenmeyer flask is most commonly used for mixing and preparing solutions that don't require a high degree of position. The flask is particularly suited to experiments that require lots of agitation because the long neck prevents splashing when the flask is swirled.
• Forming microbial cultures: Erlenmeyer flasks are commonly used to grow cell cultures because of their large surface area and excellent aeration. In microbiological experiments, most Erlenmeyer flasks are fitted with a vented closure to allow for gas exchange during incubation.
• Heating experiments: Most Erlenmeyer flasks can be heated directly on a high-quality hot plate because they resist thermal shock. This durability makes them an excellent tool for boiling or heating experiments.
• Titrations: The Erlenmeyer flask is a commonly used flask in titration, where a solution of known concentration is slowly added to a solution of unknown concentration. The conical shape of the flask reduces splashing, meaning the Erlenmeyer flask can be placed directly under a burette to allow for greater precision.
• Fermentations: Erlenmeyer flasks are often used in biotechnology labs for the fermentation of microorganisms. The narrow neck of the flask reduces the risk of contamination, and vented closure allows gas to escape as the fermentation process takes place.
• Transferring and storing liquids: The durability of Erlenmeyer flasks makes them excellent for storing and transferring solutions.
• Crystallization: Erlenmeyer flasks are typically used to crystallize certain compounds, in which a solution is prepared in the flask and then gradually cooled to create crystals.

Sharpening cap or no sharpening cap?

There are two primary variations of Erlenmeyer flask: those with a sharpening cap and those without.

The sharpening cap is a small lid that fits over the top of the Erlenmeyer flask. However, unlike a typical bung or rubber stopper, the sharpening cap contains a small piece of film that allows a pipette or needle to access the flask's contents.

Sharpening caps provide a sterile way to access the contents of a flask without having to remove the lid. This is especially important when multiple samples must be taken or added to a solution over time, as it reduces the chances of contamination or spillage.

That said, Erlenmeyer flasks with sharpening caps tend to be more expensive to produce and purchase. For experiments that don't require high degrees of accuracy or for applications that need to be performed at scale, a flask without a sharpening cap is a cost-effective alternative.

Using an Erlenmeyer flask: top tips for accurate results

Now that we've detailed everything you need to know about the Erlenmeyer flask, let's discuss how to use one. There are many different ways to use an Erlenmeyer flask, but these top tips can be applied to any experiment.

1. Thoroughly clean your Erlenmeyer flask before each use using deionized or distilled water. Using regular soap and water could introduce impurities or residue into the flask, which may affect the accuracy of your experiment.
2. Use a high-quality glass stirring rod to stir mixtures, promote even distribution, and prevent clumping.
3. Be careful. Most Erlenmeyer flasks are made of glass and can break easily. Make sure to handle with care, especially if your flask contains a corrosive liquid.
4. Don't overfill your flask. Filling an Erlenmeyer flask to the brim can increase the likelihood that you will spill your solution. It's recommended to buy a larger flask than required to allow adequate headway for shaking and heating.

Where can I find Erlenmeyer flasks?

Certified MTP offers a broad range of first-class Erlenmeyer flasks, volumetric flasks, beakers, pipettes, burettes, lab stirrers, water baths, incubators, and more. We're committed to providing our customers with only the highest quality product, and work to ensure that every use of our equipment produces accurate, reliable results for your next scientific experiment.

If you'd like to learn more about our range of high-quality products, browse our full range here. Want to ask us a question or ask us for a recommendation? Get in touch. We're always happy to help.