CHEMGLASS CG-1702-12 Addition Funnel Joint Ptfe Stopcock 14/20 Stopper

( Brand: Chemglass ), ( Manufacturer Part Number: CG-1702-12 ), ( Part Type: Stopcock Joint Stopper ), ( Unit Type: Unit ), ( Volume: 25 Ml ), ( Country Of Origin: United States ), ( Intended Use/discipline: Biological Laboratory, Dental Laboratory, Medical Laboratory, Microbiological Laboratory, Physical Laboratory )

Review CHEMGLASS Addition Funnel Ml 14/20 Joint Ptfe Stopcock Stopper

The Chemglass CG-1702-12 Addition Funnel is a precision-engineered laboratory accessory designed for seamless integration into glassware setups where controlled liquid additions are essential. Featuring a robust **25 mL capacity**, this funnel is ideal for applications requiring gradual, metered delivery of reagents, solvents, or reaction components without disrupting the primary reaction vessel. The **14/20 standard taper joint** ensures a secure, leak-proof connection to compatible glassware, including round-bottom flasks, distillation apparatuses, or reaction kettles, while minimizing dead volume and maximizing efficiency. The **PTFE (polytetrafluoroethylene) stopcock** is a standout feature, offering superior chemical resistance, low friction, and durability across a wide range of solvents, acids, and bases from aqueous solutions to highly corrosive media like hydrofluoric acid or concentrated sulfuric acid. Unlike rubber or silicone stopcocks, PTFE remains inert, non-porous, and resistant to swelling or degradation, making it a reliable choice for both routine and high-purity laboratory procedures. The **glass stopper** provides an additional layer of control, allowing for temporary sealing when the stopcock is not in use, while its smooth, polished surface reduces the risk of particulate contamination. Constructed from borosilicate glass (Type I, per USP/EP standards), the funnel is thermally stable, chemically inert, and capable of withstanding repeated autoclaving or harsh cleaning protocols, including strong oxidizing agents like chromic acid or alkaline detergents. Its **clear, uncolored glass** allows for visual monitoring of liquid levels, ensuring accurate dosing without guesswork. Whether used in organic synthesis, analytical chemistry, or pharmaceutical development, the CG-1702-12 delivers a perfect balance of functionality, precision, and longevity, making it an indispensable tool for laboratories demanding both performance and reliability.

**Pros and Cons of buying a Chemglass CG-1702-12 Addition Funnel (25/14 20 Joint, PTFE Stopcock, Stopper)**

1. **Durability and Material Quality** The addition funnel is constructed from borosilicate glass (likely Type 1 or 3.3), which is chemically resistant, heat-resistant, and durable. This makes it suitable for a wide range of laboratory applications, including corrosive reagents and high-temperature reactions.

2. **PTFE Stopcock** The PTFE (polytetrafluoroethylene) stopcock provides a tight seal and is resistant to most chemicals, reducing the risk of leaks or contamination. PTFE is also easier to clean than rubber or silicone stopcocks, making maintenance simpler.

3. **Standard Joint Compatibility** The 25/14 20 joint is a common laboratory joint size, meaning it is widely compatible with other glassware, adapters, and laboratory equipment. This makes it easy to integrate into existing setups without needing specialized fittings.

4. **Stopper Included** The inclusion of a stopper (likely a PTFE or glass stopper) ensures that the funnel can be sealed when not in use, preventing spills or contamination from dust or airborne particles.

5. **Precision and Control** Addition funnels allow for controlled, dropwise or slow addition of liquids to reactions, which is critical in titrations, slow reactions, or sensitive procedures where precise dosing is required.

6. **Reusable and Cost-Effective** Unlike disposable plastic funnels, this glass addition funnel is reusable, making it a cost-effective long-term investment for laboratories that perform frequent additions.

7. **Compatibility with Vacuum Systems** The design can often accommodate vacuum or pressure applications, depending on the setup, though this would depend on additional components like adapters or clamps.

8. **Easy to Clean** Glass surfaces are straightforward to clean and sterilize, which is essential for maintaining consistency in experimental results, especially in research or pharmaceutical settings.

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1. **Fragility** Glassware is inherently fragile and can break if dropped or subjected to thermal shock (e.g., rapid heating or cooling). This requires careful handling and storage to prevent damage.

2. **Weight and Portability** Glass funnels are heavier than plastic alternatives, which can make them less convenient for fieldwork or mobile laboratories. Moving them requires additional care to avoid breakage.

3. **Limited Chemical Resistance (Theoretical)** While borosilicate glass is highly resistant, no material is universally compatible with *all* chemicals. Extremely aggressive reagents (e.g., hydrofluoric acid, strong alkalis at high temperatures) may eventually degrade the glass over time, though this is rare with proper use.

4. **Maintenance of PTFE Stopcock** PTFE stopcocks can wear out over time, especially with frequent use or abrasive materials. They may require periodic lubrication (with a compatible grease) or replacement, adding to long-term maintenance costs.

5. **Cost Upfront** Compared to disposable plastic funnels, the initial purchase price of a high-quality glass addition funnel is higher. However, this is often justified by its longevity and performance.

6. **Specialized Storage Needs** Glassware should be stored in a way that prevents it from coming into contact with other items (e.g., in a dedicated glassware cabinet or wrapped in cloth to avoid scratches). Improper storage can lead to damage.

7. **Potential for Leaks** If the PTFE stopcock or joint is not properly lubricated or if the glass is scratched, leaks can occur. This requires regular inspection and maintenance to ensure a proper seal.

8. **Not Ideal for High-Pressure Applications** Without additional reinforcement (e.g., a pressure-rated joint or adapter), this funnel is not designed for high-pressure operations. Standard addition funnels are typically used in atmospheric or low-pressure setups.

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The **Chemglass CG-1702-12 addition funnel** is a high-quality, versatile tool well-suited for laboratory applications requiring precise liquid additions. Its borosilicate glass construction, PTFE stopcock, and standard joint compatibility make it a reliable choice for routine and advanced laboratory work. While it has some drawbacks primarily related to fragility and maintenance the benefits of durability, chemical resistance, and reusability far outweigh these limitations for most laboratory settings.

- Academic and industrial research laboratories.

- Settings where chemical compatibility and precision are critical (e.g., organic synthesis, analytical chemistry).

- Users who prioritize long-term investment over disposable alternatives.

For users who frequently handle highly corrosive or abrasive substances, or who require extreme durability, it may be worth considering additional protective measures (e.g., using a protective sleeve or ensuring proper lubrication of the PTFE stopcock). However, for standard laboratory use, this addition funnel is an excellent and practical choice.

**Final Recommendation:** Purchase the Chemglass CG-1702-12 addition funnel if you need a durable, precise, and reusable tool for controlled liquid additions in a laboratory setting. Ensure proper handling and maintenance to maximize its lifespan and performance.

Details:

Chemglass CG-1702-12 Addition Funnel 25 ml 14/20 Joint PTFE Stopcock with Stopper.

part #: cg170212 price

• $75.00

specifications plasticwarelabsuppy:

• brand: Chemglass
• mpn: Cg-1702-12
• part type: Stopcock Joint Stopper
• unit type: Unit
• volume: 25 Ml
• country of origin: United States
• intended use/discipline: Biological Laboratory, Dental Laboratory, Medical Laboratory, Microbiological Laboratory, Physical Laboratory

offer plasticwarelabsuppy:

• availability: In Stock
• sold: 0
• quantity: 1
• options: Ship-to-home
• started: May 7, 2026
• best offers: True

payments plasticwarelabsuppy:

• other
• credit card: Diners-club
• wallet: Google-pay

returns plasticwarelabsuppy:

• time: 30 Days
• paid by: Buyer
• policy: Returns Accepted
• method: Money back

general plasticwarelabsuppy:

• condition: New Open box
• Medical, Lab Dental Supplies > Glassware Plasticware > Other Medical Lab Glassware

seller plasticwarelabsuppy:

• # reviews: 2435
• city: Ponder, Texas
• rating: 100.0%

shipping plasticwarelabsuppy:

• cost: $0.00
• carrier: USPS
• type: Fixed
• transit: 4-9 Days
• service: USPS Ground Advantage, Expedited
• class: Standard, Expedited

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