What is the Difference Between Crucible and Evaporating Dish?

The main difference between a crucible and an evaporating dish lies in their uses and the materials they are made of:

1. Crucible:

• Used for heating non-aqueous substances, such as melting non-corrosive salts, burning precipitation, and carbonizing or ashing complex samples.
• Made of materials resistant to high temperatures, such as ceramic (with an upper temperature limit of about 800 degrees) or quartz (which can withstand temperatures above 1000 degrees).
• Can be heated directly or placed in a high-temperature heating furnace.
• Often used in conjunction with crucible tongs for handling.

1. Evaporating Dish:

• Used for the evaporation of solutions and supernatant liquids.
• Typically made of ordinary glass, porcelain, or borosilicate glass, with a use temperature below 400 degrees.
• Can be heated directly with an open flame (for ceramic evaporating dishes) or covered with an asbestos net for heating (for glass evaporating dishes).
• Generally held by hand, with glass rods or spoons used to transfer reagents.

In summary, a crucible is designed for heating non-aqueous substances and is made of materials resistant to high temperatures, while an evaporating dish is used for evaporating solutions and is typically made of glass or porcelain, with a lower temperature tolerance.

Comparative Table: Crucible vs Evaporating Dish

Here is a table comparing the differences between a crucible and an evaporating dish:

Keep in mind that while both crucibles and evaporating dishes are laboratory glassware, they have different uses and material requirements. A crucible is designed for heating non-aqueous substances and can withstand high temperatures, while an evaporating dish is mainly used for evaporating solutions.