What is the name of the funnel used with a vacuum apparatus for solids testing?

The Buchner funnel is specifically designed for use with vacuum filtration apparatus, particularly in solids testing and laboratory settings. Its wide, flat bottom and perforated plate allow for efficient collection of solids while facilitating quick filtration when used with a vacuum system. The vacuum draws the liquid through the filter medium, usually placed inside the funnel, allowing for the rapid separation of solids from liquids. This design enhances both the speed and efficiency of the filtration process, making the Buchner funnel a standard tool in laboratories for various types of solid-liquid separations.

In contrast, the other types of funnels mentioned serve different purposes. The filter funnel, while also used for filtration, is typically not designed for vacuum applications and has a more conical shape. A micro funnel is generally used for very small volume applications, and a straining funnel is used for removing larger particles from liquids but does not utilize a vacuum system. Each of these alternatives lacks the specific design features and intended use inherent to the Buchner funnel, emphasizing why it is the correct choice for the question regarding solids testing in a vacuum apparatus.