Video Transcript
What piece of labware is shown in the image below? (A) Volumetric flask, (B) beaker, (C) Erlenmeyer flask, (D) round-bottom flask, or (E) watch glass.
The image shows a piece of lab glassware with a flat base, a conical body, and a thin neck. We can identify this piece of glassware from its shape. Pieces of labware that can hold liquids and have flat bases and so can stand on their own without support come in a variety of shapes.
Volumetric flasks have a very long thin neck and a bulbous bottom with one graduation mark. Beakers have a short, wide, cylindrical shape with multiple graduations. Erlenmeyer flasks, also known as conical flasks, have a flat base, a conical body, and a thin short neck. They may have multiple graduations, and in some cases, they may not, for example, in this image. Graduated cylinders have a flat base, are cylindrical in shape, but are longer and thinner than beakers. They tend to have more finely divided graduations than beakers.
Beakers and Erlenmeyer flasks are often similar in their widely spaced volume markings. This makes them more useful for approximate volume readings. And they are not as accurate as graduated cylinders. Erlenmeyer flasks have slightly different applications to the use of beakers. Their thin necks help prevent splashing in reactions that need to be stirred or swirled.
We have identified the Erlenmeyer flask as the answer based on its structure. We know that beaker is not the answer because beakers do not have a thin neck. And we can rule out volumetric flask because it only has one graduation as well as a long thin neck and a bulbous bottom instead of a conical body. A round-bottom flask has what the name suggests, a round bottom. It cannot stand on its own and must rest on a round mantle or be clamped in place. Finally, a watch glass, which looks like a very shallow, curved, glass dish, is used to hold small amounts of solids.
The question asked, “Which piece of labware is shown in the image below?” The answer is (C) Erlenmeyer flask.
