I’m surprised that I’ve gotten this far in my scientific blog without talking about beakers (though I have mentioned them in blog posts in the past, I haven’t had a post specifically about beakers). From what I’ve seen from depictions of scientists in pictures or fiction, beakers are seen as the typical chemistry equipment, though they’re not as distinctive in silhouette as the Erlenmeyer flask or volumetric flask. Like the other two, they are used to measure and store liquids. They are definitely less accurate or precise (using the scientific definition I mentioned in a previous post) than the volumetric flask, buret, volumetric pipette, or micropipette. They’re still ‘read’ the same way, and it can be difficult without a lot of experience to determine the correct volume (I went into more detail about the meniscus in a previous post).
Despite the fact that the accuracy is worse, we tended to have more beakers available, and used them more often, so that, at least, may explain why beakers are considered the essential chemistry accessory. I find it easier to cause chemical reactions in a beaker, partly because adding the ingredients is easier than through the slim neck of a volumetric flask or an Erlenmeyer flask and partly because mixing was overall easier. They also came in a number of different sizes, from 5 mL to 5 L, all of which I saw in various school labs. These two extremes weren’t very common sizes, though—I only saw one of each, though when we were doing microchemistry (chemistry on a small scale with small amounts of ingredients) we used a 15 mL beaker on occasion. Their popularity is also probably helped by the fact that it’s easy to leave the results of an experiment for another day (assuming it’s not dangerous to leave it around), particularly since the most common size for a beaker (150 mL or 250 mL, at least in our college laboratories) is right around the right size for a watchglass to cover, which helps prevent evaporation. Unlike volumetric flasks, a number of different volumes can be chosen, though the accuracy is better if the volume is closer to the maximum volume (which impacts what size of beaker is used). However, just like with the accuracy of the volume contained, the prevention of evaporation is not as thorough as it could be (stoppers for the Erlenmeyer or volumetric flasks exist).
So, beakers would not be appropriate for quantitative chemistry on their own, in which you need accurate measurements of the volume (unless a more accurate pipet or buret is used), and doesn’t work as well when storing the products of the reaction—but, on the other hand, if you’re going for qualitative chemistry, looking for whether the chemicals react or do not react, or a reaction involving color, or even planning to put the product in specific instruments, a beaker is a good choice. Beakers can, however, be combined with equipment that can be more accurate, hold more volume than your average volumetric piece of equipment, and can easily be combined with a heating mantle, stir bar, or glass stirring rod.
Where was the first place you’d seen a beaker?