Round Bottom Flask Two Neck Jointed BORO 3.3 Glass

Description

Round Bottom Flask, Two Neck Jointed, BORO 3.3 Glass, also known as a double-neck round-bottom reaction flask, is designed for laboratory heating, mixing, reflux, distillation and chemical reaction procedures requiring more than one connected component. The two-neck arrangement enables compatible jointed laboratory equipment to be installed simultaneously, providing greater flexibility when assembling reaction and separation systems.

The flask is manufactured from high-quality BORO 3.3 low-expansion borosilicate glass that conforms to ISO 3585 requirements for borosilicate glass 3.3. It also meets the glass quality requirements of ASTM E438 Type I, Class A, which classifies low-expansion borosilicate glass used in laboratory apparatus. These recognised ISO and ASTM glass standards define important material characteristics, including thermal expansion, chemical durability, density and temperature-related properties.

BORO 3.3 glass provides strong resistance to water, acids, saline solutions and many commonly used laboratory chemicals. Its low coefficient of thermal expansion supports reliable performance during controlled laboratory heating and cooling processes. As with all laboratory glassware, rapid or uneven temperature changes should be avoided to reduce thermal stress and protect the flask from damage.
The spherical body provides a large and evenly curved heating surface, helping distribute heat more uniformly than vessels with flat bases. This shape also promotes natural liquid circulation and efficient mixing when the flask is used with an appropriate magnetic stirrer, overhead stirrer, heating mantle, water bath or oil bath. The flask must be supported using suitable clamps because the round-bottom body cannot stand independently on a flat surface.

Its two jointed necks allow the user to configure the flask for more complex laboratory procedures. One neck may be connected to a condenser while the second accommodates a dropping funnel, thermometer adapter, gas inlet, vacuum adapter or another compatible jointed component. This makes the flask particularly useful for reflux reactions, controlled reagent addition, reaction temperature monitoring, distillation and procedures conducted under a controlled atmosphere.

The clear glass construction allows users to observe sample movement, boiling behaviour, colour changes, precipitation and other visible reaction stages. Before use, the flask should be inspected for cracks, chips, scratches or damaged joints. Joint sizes, flask capacity and accessory compatibility should be confirmed before assembling the apparatus, and all connected components should be properly clamped and supported.

LabChoice Australia supplies the Two Neck Jointed Round Bottom Flask for chemistry, research, education, industrial testing and general scientific laboratories requiring ISO and ASTM quality BORO 3.3 reaction glassware. Its low-expansion glass construction, versatile two-neck configuration and rounded heating surface make it suitable for dependable laboratory reaction, heating and separation workflows.