A laboratory mortar and pestle is a tool used in scientific and medical laboratories to grind and mix materials into fine powders or pastes. A mortar and pestle typically consists of two components: a hard, heavy bowl-shaped container made of ceramic, glass, or other materials, called a mortar, and a long, rounded tool made of the same material, called a pestle.

A laboratory mortar and pestle with a size of 11cm generally means that the diameter of the mortar bowl is approximately 11 centimeters. This size is commonly used for grinding and mixing small to medium amounts of materials.

The mortar and pestle is used by placing the material to be ground into the mortar, then using the pestle to apply pressure and grind the material into a fine powder or paste. The friction between the material and the mortar, along with the crushing and grinding action of the pestle, breaks the material down into smaller and smaller particles until it reaches the desired consistency.

Laboratory mortars and pestles are used in a variety of scientific and medical applications, such as grinding solid samples for analysis, preparing samples for microscopy, or crushing and blending compounds for chemical reactions. They are also used in the preparation of herbal remedies and in food preparation for grinding spices and other ingredients.