Accurate nitrogen determination is crucial in many scientific and industrial applications, from food analysis to environmental testing. The Kjeldahl flask is a fundamental piece of equipment in this process. Selecting the right flask ensures reliable results, consistent performance, and safe laboratory operation.
- StonyLab Kjeldahl Flask is commonly used as an air condenser during digestion stage and reduces entrainment during the distillation stage of the Kjeldahl process; ideal for determination of nitrogen, etc
- Capacity: 500 ml
- With 24/40 standard taper outer Joints
- Made of borosilicate glass; heavy duty, heavy all and durable; maximum withstand temperature 200°C
- Designed for nitrogen determination as per Kjeldahl method
- Made of high quality Borosilicate glass
- 100mL capacity
- Long neck, round bottom
- Round bottom and long neck
- Tooled for uniform rubber stopper fit
- Flasks can be used in ASTM E 258 procedure
- Reusable
- StonyLab Kjeldahl Flask is commonly used as an air condenser during digestion stage and reduces entrainment during the distillation stage of the Kjeldahl process; ideal for determination of nitrogen, etc
- Capacity: 100 ml
- With 24/40 standard taper outer Joints
- Made of borosilicate glass; heavy duty, heavy all and durable; maximum withstand temperature 200°C
- Capacity: 50ml
- Long neck round bottom Kjeldahl flask
- Standard 24/40 ground glass joint
- Product for nitrogen determination as per Kjedahl method
- Designed for nitrogen determination as per Kjeldahl method
- Made of high quality Borosilicate glass
- 800mL capacity
- Rounded Base
- LABORATORY FLASK: Corning provides a number of PYREX brand flasks for special purpose applications
- SAFE & DURABLE: Offering superior heat, chemical and thermal shock resistance
- PERMANENT MARKINGS: Permanent white enamel to resist chemical attack during lab usage
- EASY TO CLEAN: The reusable glass scientific flasks are easy to clean and can be sterilized safely in autoclaves at 121°C, making them ideal for repeated use in busy lab environments.
- The pear-shape reaction flask, capacity of 200ml, with glass stopcock which is connecting to a vacuum or inert gases source.
- With 24/40 top taper outer joint allowing material to be added to a flask or attaching a reflux condenser for reaction.
- The schlenk reactionf lask is made of high quality borosilicate glass, heavy-wall designed, high transparence, high transparence, durable and reusable.
- In a reaction setup, the pear-shape schlenk flask may use with an addition funnel, reflux condenser, magnetic stirring shaft and bars.
- Designed for nitrogen determination as per Kjeldahl method
- Made of high quality Borosilicate glass
- 500mL capacity
- Socket size: 24/29
- Designed for nitrogen determination as per Kjeldahl method
- Made of high quality Borosilicate glass
- 300mL capacity
- Rounded Base
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Last update on 2026-10-24 / Affiliate links / Images from Amazon Product Advertising API
How to Choose the Best Lab Kjeldahl Flasks
Capacity
Kjeldahl flasks come in various sizes, typically ranging from 100 mL to 2000 mL. The appropriate capacity depends on the sample size and the volume of reagents required for your specific analysis. For routine analyses with smaller samples, a 300 mL or 500 mL flask is often sufficient. Larger volumes may necessitate a 1000 mL or 2000 mL flask.
Material and Construction
Most Kjeldahl flasks are made from borosilicate glass, known for its resistance to thermal shock and chemical corrosion. This durability is essential for withstanding the high temperatures and acidic conditions common in the Kjeldahl digestion process. Look for flasks with a sturdy construction, clear graduations for accurate volume measurement, and a long neck to minimize sample loss during boiling.
Joint Size and Compatibility
If your setup involves connecting the flask to other apparatus, such as a distillation unit or a condenser, ensure the flask has the correct joint size. Standard ground glass joints (e.g., 24/40) are common. Verify that the joint size matches your existing equipment to ensure a secure and leak-free connection.