Which glassware is designed to deliver a known volume when filled to a mark?

• A. Beaker
• B. Volumetric flask
• C. Desiccator
• D. Pipette

Answer: (B)

Delivering a known volume relies on a glassware item that is calibrated to a single, precise mark. A volumetric flask is built with one calibration line in the neck, so when the liquid is filled exactly to that mark, the volume is the stated amount. This design, paired with careful temperature control (volumes are specified at a reference temperature, commonly 20°C), makes it ideal for making standard solutions with accurate concentrations.

Other glassware serves different roles: a beaker is for general work with approximate volumes, not precise measurements; a desiccator is for drying and storage, not volume delivery; a pipette can transfer a specific volume, but its accuracy depends on technique and the device, whereas the volumetric flask is specifically intended for delivering a known volume by filling to a single mark.