Click on a name below to read a description of the glassware and what it is used for.
Beaker | Erlenmeyer Flask | Distilling Flask | Liebig Condenser | Test Tube | Funnel | Stirring Rod
Beakers are glass cylinders used for mixing and heating chemicals. They are usually made of a type of glass (such as Pyrex®)that can withstand high temperatures. The diameter of a beaker is the same from top to bottom. While many beakers do have markings on the side indicating volume, these markings (or graduations) are only approximate values; they should not be used for measuring exact volumes.
Erlenmeyer flasks are glass conical containers used for mixing, heating, and storing chemicals. They are usually made of a type of glass (such as Pyrex®) that can withstand high temperatures. The flask is shaped like a cone with the opening at the top of the flask being the narrow end of the cone. While many Erlenmeyer flasks have markings on the side indicating volume, these graduations are only approximate values; they should not be used for measuring exact volumes.
The Erlenmeyer flask was invented by the German chemist, Richard Erlenmeyer. These flasks are useful in titration experiments, where the shape of the flask enables the contents to be swirled with a minimum of overflow. Erlenmeyer flasks are also useful in the preparation of supersaturated solutions; the conical shape slows the rate at which the contents cool, and helps to minimize premature crystallization of the solute particles.
Distilling flasks are made of glass, and consist of three main parts: a spherical base, a cylindrical neck, and a cylindrical sidearm that is connected to the flask neck. They are usually made of a type of glass (such as Pyrex®) that can withstand high temperatures.
The distilling flask is used to separate liquid mixtures by distillation. Distillation is the process of separating mixtures based on the difference in boiling points of the components of that mixture. As the flask and the contents are heated, each component of the mixture changes from the liquid phase to the gas phase (components change in order from lowest boiling point to highest boiling point). As the molecules in the gas phase rise, they are usually routed through the sidearm into a condenser (the top of the neck is usually sealed with a cork or rubber stopper).
Liebig condensers are made of glass and consist of two main parts: a straight cylindrical tube surrounded by an enclosed glass jacket with two sidearms at either end of the jacket on opposite sides.
The Liebig condenser was invented by Justus Baron von Liebig, a German chemist of the 19th Century. All condensers (in general, not just Liebig-type) are used to cool gases to a point where they will liquefy, or condense, back into their liquid form, so that they may be collected in a separate container. Most commonly, condensers will be used in conjunction with a distilling flask or similar piece of glassware. The substance being condensed travels through the central cylindrical tube. The outer jacket is filled with a continuous flow of cool water from the lab sink. The water comes in through the sidearm at the bottom end of the flask, and exits out of the sidearm at the top of the flask.
Test tubes are narrow glass cylinders, closed at one end, that are used for mixing, heating, and storing small quantities of chemicals. They are usually made of a type of glass (such as Pyrex®) that can withstand high temperatures. Test tubes come in many different sizes, which are usually given as the tubes' dimensions (diameter × height, both expressed in millimeters).
Funnels can be made of glass or plastic. Plastic funnels are commonly found in high school laboratories due to the durability of the plastic material. However, glass is a preferable material, due to its resistance to chemical reactivity. A funnel consists of two main parts: a conical-shaped top and a long cylindrical stem at the bottom. Funnels are used for transferring liquids (sometimes solids) to containers with small openings, in order to prevent spills. They can also be used with filter paper in the process of filtration. Funnels come in many different sizes, depending on the amount of material being poured through.
Stirring rods are usually made of glass. Stirring rods are used to stir mixtures and facilitate the pouring of liquids. Glass is the material of choice for stirring rods due to its resistance to chemical reactivity. When placed across the top of a beaker so that it lies along the spout, stirring rods can help prevent the liquid being poured from dribbling down the outside of the container.