Laboratory Flasks

Laboratory flasks are a family of glass or plastic containers with a narrow neck used for mixing, heating, measuring, and storing liquids in scientific work; common types include Erlenmeyer, volumetric, and cell culture flasks.

Flat Bottom Flask

A flat bottom flask (also known as a Florence flask) is a staple of laboratory glassware designed specifically for stability. Its unique shape—a spherical body with a flattened base—allows it to stand upright on a flat surface without the need for support rings or clamps.

Key Features

• Material: Usually made of borosilicate glass (like Pyrex), which is resistant to chemical corrosion and thermal shock.
• Stability: The flat base provides a low center of gravity, making it much harder to tip over than its round-bottomed cousin.
• Neck Design: Typically features a long, narrow neck that can be closed with a stopper or connected to other glassware using ground glass joints.

Common Uses

1. Storage: Its ability to stand alone makes it ideal for holding reagents or prepared solutions for short periods.
2. Heating Liquids: It is frequently used on hot plates. The flat bottom ensures better surface contact with the heating element compared to a round flask.
3. Mixing & Swirling: The spherical body allows for efficient mixing of liquids while the neck prevents splashing.
4. Simple Distillation: It can serve as a boiling flask in basic distillation setups, though it is less common in professional high-vacuum setups.

Round Bottom Flask

A round bottom flask (also known as an RB flask) is the workhorse of organic chemistry and research laboratories. Its spherical shape is not just iconic; it is engineered to handle extreme temperatures and pressure changes that would cause other glassware to crack.

Key Features

• Material: Almost exclusively made of borosilicate glass for high thermal shock resistance.
• Spherical Base: Unlike a flat bottom flask, the round base ensures that heat is distributed uniformly across the liquid, preventing “hot spots” that can lead to uneven boiling or decomposition of sensitive chemicals.
• Ground Glass Joints: Most professional RB flasks feature standardized joints (e.g., 24/40) that allow them to be “clicked” into airtight systems like condensers or addition funnels.