Evaporating dish

Evaporating Dish

3D rendering of an evaporating dish

An evaporating dish is a piece of laboratory equipment used for the evaporation of solutions and supernatant liquids, and sometimes to their melting point. They are typically made of porcelain, glass, or other materials that can withstand high temperatures.

Design and Material

Evaporating dishes are usually made from materials that can endure high temperatures, such as ceramic or borosilicate glass. The design of an evaporating dish is simple, featuring a shallow, wide mouth to allow for the rapid evaporation of liquids. The wide surface area facilitates the evaporation process by increasing the exposure of the liquid to air.

Uses in the Laboratory

Evaporating dishes are commonly used in chemistry laboratories for the following purposes:

• Evaporation of Solvents: To remove solvents from a solution, leaving behind the solute.
• Concentration of Solutions: To concentrate a solution by evaporating the solvent.
• Crystallization: To promote the crystallization of solutes by evaporating the solvent.
• Drying Precipitates: To dry a precipitate by evaporating the liquid.

Handling and Safety

When using an evaporating dish, it is important to handle it with care, especially when it is hot. The following safety precautions should be observed:

• Use tongs or heat-resistant gloves to handle hot dishes.
• Place the dish on a heat-resistant surface when heating.
• Avoid rapid temperature changes to prevent cracking.

Related Equipment

Evaporating dishes are often used in conjunction with other laboratory equipment, such as:

• Bunsen burner: For providing heat to the dish.
• Tripod stand: To support the dish above the heat source.
• Wire gauze: To distribute heat evenly and prevent direct contact with the flame.

Related Pages

• Crucible
• Beaker
• Laboratory glassware
• Porcelain