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USA Lab
Round Bottom Flask - 1 neck 24/40 - Various Sizes
$20.00 - $130.00
In stockPrice varies by Size.
Single-neck round bottom flask with a 24/40 standard taper ground glass joint, available in 250 ml, 500 ml, 1000 ml, 2000 ml and 5000 ml. The 24/40 joint mates directly with 24/40 rotovap adapters, condensers and stoppers, including the 2L rotovap bump trap adapter listed separately.
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Description
Single-neck round bottom flask with a 24/40 standard taper ground glass joint. Round bottom flasks are the working vessel for distillation, reflux and rotary evaporation: the curved base distributes heat evenly and gives no corner for material to sit in, and the ground joint couples directly to condensers, adapters and stoppers of the same taper without additional fittings.
The 24/40 designation is the standard taper size – nominally 24 mm across the joint at its widest point with a 40 mm ground length. It is the same joint size used by the 2L rotovap bump trap adapter listed separately in this catalogue, and by the RE-200A rotovap’s boiling flask flange.
Capacities offered:
- 250 ml
- 500 ml
- 1000 ml
- 2000 ml
- 5000 ml
We have not been supplied with a stated glass grade, wall thickness or thermal specification for this flask, and we do not publish figures we cannot source. If your protocol requires a documented borosilicate 3.3 specification or a vacuum rating in writing, ask for the manufacturer’s written specification before ordering.
Frequently asked questions
What sizes are available?+
250 ml, 500 ml, 1000 ml, 2000 ml and 5000 ml, each priced individually.
What does 24/40 mean?+
It is a standard taper ground glass joint designation: nominally 24 mm diameter at the widest point of the joint, with a 40 mm ground length. Any 24/40 male fitting - condenser, adapter, stopper, bump trap - will seat in this flask's neck.
Will it fit a rotary evaporator?+
It will mate with any 24/40 joint, which includes the 2L rotovap bump trap adapter we list and the RE-200A boiling flask flange size. It will not fit units specified with a different flange, such as the 5L RE-501 at 50 mm. Check the flange size in your evaporator's manual first.
What glass is it made from?+
The data supplied to us does not state a glass grade, so we do not publish one. Ask for the manufacturer's written specification before specifying this flask for high thermal shock work or for a documented vacuum application, rather than assuming a grade.
How many necks does it have?+
One. Multi-neck flasks, which allow a condenser, a thermometer and an addition funnel to be run at once, are a different item.
Does it come with a stopper or clamp?+
No. It is listed as the flask alone. Joint clamps and stoppers are ordered separately.
Related products
Spherical Joint Round Bottom Receiving Flask - 1 neck 35/20
Single-neck round bottom receiving flask with a 35/20 spherical (ball) joint, listed in 250 mL, 500 mL, 1 L and 2 L. Spherical joints clamp rather than taper, so the flask can sit at an angle to the take-off. Glass grade is not documented and no ball-joint clamp is listed as included.
2-Neck Round Bottom Flask – Borosilicate 3.3 Glass
Two-neck round bottom flask in 3.3 borosilicate glass, listed in nine size and joint combinations from 250 mL to 10 L. Smaller sizes are listed at 24/40; the 2 L, 5 L and 10 L options pair a 34/45 or 45/50 centre joint with a 24/40 side joint.
