Graduated cylinder

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A graduated cylinder (Grad or graduate for short), also referred to as a measuring cylinder, is a type of laboratory glassware comprised of a tall cylinder with a range of calibrated markings that is used for visually measuring the volumes of liquids in a quantitative manner. A graduated cylinder can be made of translucent plastic or borosilicate glass such as Pyrex. Often, the largest graduated cylinders are made of polyethylene or other rigid plastic, making them lighter and less fragile than glass, but more difficult to sterilize.

1 Description
2 Usage
3 Ranges and sizes
4 Alternative instruments

[edit] Description

The top usually has a small curled lip to allow easy pouring of liquids, and the bottom is usually anchored with a wide base, to keep the cylinder from easily tipping. The volumes of liquids graduated cylinders can handle range from a few milliliters to many liters. A simple rain gauge uses a cylinder with marks calibrated in millimeters or inches of collected rain.

[edit] Usage

To read precisely the quantity of liquid collected, the cylinder is heald at eye level, and the fluid's meniscus is read against the calibrated graduation marks printed, embossed or etched along the cylinder.

[edit] Ranges and sizes

A well equipped laboratory will have multiple cylinders in a variety of ranges and sizes. Generally, as a cylinder is narrowed, more precise measurements can be obtained in readings, as the graduation markings are farther apart for the same volume. Dispensing burettes are often used to provide more precise measurement options than ordinary graduated cylinders (fraction of a drop). Beakers may also be calibrated and marked with graduations for gross measurements (within a milliliter or so).

[edit] Alternative instruments

A burette is a type of graduated cylinder for precisely measuring the amount of liquid released through a valve at the bottom, rather than the volume collected from the top.

Laboratory equipment