Parts of a Graduated Cylinder

A graduated cylinder is used in a variety of laboratory settings. The main function of a graduated cylinder is to measure out set amounts of liquids, including potentially acidic liquids. The design of the cylinder allows for rough measurements to be made and allows for pouring of the liquids. There are a few component parts that make up a graduated cylinder.

Parts

• The main cylinder part of the graduated cylinder is the long tube portion of this piece of lab equipment. The cylinder can be made from different materials, and different types are designed to work with certain liquids. Glass and Pyrex are sometimes used to make the cylinder. However, polypropylene is sometimes used because it is a plastic polymer capable of withstanding a variety of chemicals. Polymethylpentene is also used sometimes, according to AbsoluteAstronomy.com, because of its clarity, lightness and resistance to breaking if dropped.

  Another part is the base of the cylinder, which helps to hold the cylinder in place while placed on a flat surface. Some bases are part of the physical cylinder and made of the same material. Other bases are plastic and allow the cylinder part to be placed inside of the base.

  The third piece of the cylinder is the bumper guard which protects the cylinder from cracking or breaking if the cylinder tips over. The bumper is usually movable and can slide up and down the cylinder but is generally kept on the upper half of the tube.

Features

• In addition to a bumper guard and a base, the cylinder also has markings on it allowing for measurements of liquids. Usually these measurements are displayed as printed-on dashes and lines on the cylinder. Some may also include numerical reference points on the cylinder surface.

  Another feature that some graduated cylinders have is a small spoutlike lip on the top opening of the cylinder. This can aid in pouring liquid out of the cylinder without spilling it.

Misconceptions

• It is a misconception that graduated cylinders are precise in their measurements. While they can be quite accurate, when precise sample sizes are needed, other equipment should be considered, such as pipettes and volumetric flasks.

Warning

• The materials that the parts of the cylinder are made of may or may not be resistant to chemicals or heat. For example, polypropylene is good for containing many kinds of chemicals and is resistant to breaking; however, it is not resistant to heat so it cannot be exposed to open flames or be placed in a cleaning device such as an autoclave. You should always check with the manufacturer's specifications before using a graduated cylinder in a lab setting.

Sizes

• Graduated cylinders come in a variety of sizes, usually measured in milliliters (ml). Common sizes include 10 ml, 25 ml and 100 ml.