Description
Round-bottom flask 250 ml with two necks is a laboratory vessel for distillation, reflux and multi-component reactions. It combines a vertical centre neck finished to NS 24/29 with a side neck angled at 20° and ground to NS 14/23, allowing convenient attachment of condensers, thermometers or addition funnels. Made from clear borosilicate glass 3.3 by manufacturer Witeg, the flask is suited to routine heating and cooling cycles in synthetic and analytical work. The nominal capacity of 250 ml (0,25 l) supports medium-scale preparative chemistry and solvent recovery. Supplied as a single piece with a net weight of 0,148 kg, it fits standard clamps and heating mantles. Two-neck round-bottom flasks of this type are used for organic synthesis, solvent distillation, crystallisation work-ups and as receiving flasks in vacuum trains. The spherical body promotes even heating and efficient mixing with magnetic stirrers, while the ground-glass joints provide reliable vapour-tight connections when properly sealed.
This article is part of Round-bottom flasks, in Beakers & flasks. See also Flat-bottom flasks.
Key features
- Pack size: 1 pc
- Nominal volume: 250 ml
- Material: Clear borosilicate glass 3.3
- Number of necks: 2
- Centre neck: NS 24/29
- Side neck: NS 14/23 angled 20°
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Questions about Round bottom flask 250 ml two necks CN ST 24/29 +
What is this article?
Round bottom flask 250 ml two necks CN ST 24/29 + is the article on this page. Luminix Health distributes Witeg for laboratory use. It sits in Round-bottom flasks, inside Beakers & flasks, in Labware.
A round-bottom flask is the heating flask of a distillation or a reflux. The curved wall takes the heat, and the ground neck connects to a still head or a condenser. The joint size, not only the volume, has to match the rest of the set.
A beaker is an open working vessel: easy to pour, poor as a measure. An Erlenmeyer flask has a flat base and a conical wall so a liquid can be swirled without climbing out. A round-bottom flask is for heating under a condenser, because the heat meets a curved wall and the joint at the neck connects to the rest of the glassware. Borosilicate is the glass that survives the temperature change. These forms are listed under ISO laboratory glassware.
Which category should I open next?
The category is Beakers & flasks. The sub-category is Round-bottom flasks. The catalogue is Labware.
Shelves beside this one are Beakers, Erlenmeyer flasks, Reaction vessels & jacketed vessels, Flat-bottom flasks, Flasks (other) and Beaker & flask accessories.
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The seven catalogues are Labware, Lab chemicals, Lab instruments, Lab consumables, Chromatography equipment, Lab safety equipment and Life Science & Microbiology.