Precise, drop-wise addition of reagents is a fundamental requirement for controlled chemical reactions and titrations. LabFriend provides a specialized selection of dropping funnels, located within the distillation and synthesis section of our distillation, separation, and filtration department. These professional-grade glass instruments are engineered to deliver exact volumes under both atmospheric and closed-system conditions.
Why Choose Professional Dropping Funnels?
Our curated collection of addition hardware is designed for chemical durability, leak-proof sealing, and fine flow regulation:
- Cylindrical Design for Accuracy: We stock Lenz-Laborglas Cylindrical Dropping Funnels in capacities ranging from 25 mL to 250 mL, providing a clear vertical scale for monitoring addition rates.
- Pressure Equalization: Utilize Lenz-Laborglas Dropping Funnels with Pressure Equalization Tubes, essential for adding reagents to closed reaction systems or under vacuum without disrupting internal pressure.
- High-Precision Control: Many models, including the ISOLAB 100 mL Cylindrical Funnel, feature PTFE stopcocks which offer superior chemical resistance and require no grease, preventing sample contamination.
- Standardized Fitment: Our funnels come equipped with NS 19/26 or NS 29/32 ground glass joints, ensuring seamless integration with standard laboratory flasks and condensers.
LabFriend supplies dropping funnels from manufacturers trusted globally for glassware excellence:
- Lenz-Laborglas: German-engineered borosilicate specialists, providing a comprehensive range of cylindrical and pressure-equalizing dropping funnels.
- ISOLAB: Providers of high-quality laboratory glassware, offering cylindrical funnels with precision PTFE stopcocks for smooth reagent delivery.
Controlled addition is the key to managing exothermic reactions; to further enhance your synthesis and distillation setup, we recommend exploring these related categories:
- Reaction & Distillation Components: Build complete synthesis rigs using ISOLAB vacuum adapters and Lenz-Laborglas drying tubes.
- Distillation Accessories: Ensure smooth boiling during your reactions using J.P. Pöllath boiling stones or Lenz gas inlet tubes.
- Solvent Storage & Handling: Securely manage the volatile reagents intended for your dropping funnels using DWK Duran or SCAT safety systems.
- Laboratory Timers: Precisely time your addition rates to ensure reaction stability and optimal product yields.
Unsure if a standard cylindrical funnel or a pressure-equalizing version is required for your specific reaction setup? Our team provides local technical support to help you find the perfect addition solution with fast shipping and competitive pricing.
Frequently Asked Questions
1. When is a pressure-equalizing dropping funnel necessary?
Pressure equalization tubes, found on specialized Lenz-Laborglas models, allow the pressure above the liquid in the funnel to remain the same as the pressure in the reaction flask, enabling addition in closed systems.
2. What are the benefits of a PTFE stopcock?
PTFE stopcocks, like those on ISOLAB funnels, do not require joint grease, which eliminates a common source of sample contamination and prevents the stopcock from "freezing" or sticking.
3. What material are these funnels made from?
All dropping funnels from Lenz and ISOLAB are manufactured from high-quality borosilicate glass, providing excellent thermal shock resistance and broad chemical compatibility.
4. Can I use these funnels for vacuum distillations?
Yes, provided you select a model with a pressure equalization tube and secure NS ground joints, these funnels are designed to operate safely under reduced pressure conditions.
