CHEMGLASS 33985-1L Vwr Pyrex Erlenmeyer Flask Male Stj 40/35 1000

( Brand: Chemglass ), ( Manufacturer Part Number: 33985-1L ), ( Unit Type: Unit ), ( Country Of Origin: United States ), ( Intended Use/discipline: Biological Laboratory, Dental Laboratory, Medical Laboratory, Microbiological Laboratory, Physical Laboratory )

Review CHEMGLASS Vwr Pyrex Erlenmeyer Flask 40/35 Male Stj 1000 Ml

The **Chemglass CG-33985 1-Liter VWR Pyrex Erlenmeyer Flask with 40/35 Male Standard-Taper Joint (STJ)** is a precision-engineered laboratory glassware essential for a wide range of chemical, biological, and analytical procedures. Crafted from durable **Pyrex borosilicate glass (Type 3.3)**, this flask is designed to withstand extreme temperature fluctuations, thermal shock, and harsh chemical environments, ensuring reliability in both routine and demanding applications. The **1-liter capacity** provides ample volume for medium-scale reactions, titrations, or sample preparations, while the **40/35 male STJ** allows for seamless compatibility with a variety of ground-glass joints, including adapters, condensers, funnels, and other laboratory accessories, facilitating efficient and leak-proof connections. The **Erlenmeyer shape**, characterized by its conical base and narrow neck, optimizes mixing and swirling of contents, reducing splashing and minimizing evaporation during stirring or heating. The **smooth, polished interior** promotes even heat distribution when used with a hot plate or heating mantle, while the **graduated markings** (if present on the model) enable precise volume measurements, though this particular item is typically ungraduated for general-purpose use. Constructed to meet **ASTM E438 standards**, this flask is free from optical imperfections, ensuring clarity and accuracy in visual observations. Its **robust construction** and **chemical resistance** make it ideal for applications such as crystallization, dissolution, and preliminary filtrations, as well as serving as a versatile container for storing or transporting liquids in laboratory settings. Whether used in academic research, industrial synthesis, or quality control testing, this flask exemplifies the durability and precision demanded by modern scientific workflows.

### **Pros and Cons of buying a Chemglass 33985-1L VWR Pyrex Erlenmeyer Flask (40/35 Male STJ, 1000 mL)**

1. **Durability and Chemical Resistance** Made from **Pyrex borosilicate glass**, this flask is highly resistant to thermal shock, chemical corrosion, and mechanical stress, making it suitable for a wide range of laboratory applications, including heating, stirring, and reactions involving strong acids, bases, or organic solvents.

2. **Standardized Dimensions** The **1000 mL capacity** and **40/35 male standard taper (STJ) joint** ensure compatibility with common laboratory glassware and accessories, such as condensers, funnels, and adapters, reducing the need for additional adapters or custom fittings.

3. **Heat Resistance** Can withstand **high temperatures** (up to 500 C when properly annealed), making it ideal for boiling, refluxing, and heating under controlled conditions without warping or breaking.

4. **Brand Reputation** **Chemglass Systems** is a well-known manufacturer of high-quality laboratory glassware, known for precision engineering and reliability. VWR (a major distributor) further ensures quality control and availability of replacement parts if needed.

5. **Versatility** Suitable for **titrations, mixing, filtration, and as a reaction vessel** in both general and analytical chemistry. The **flat bottom** provides stability, while the **neck design** allows for easy attachment to other glassware.

6. **Easy Cleaning and Sterilization** Glass is **inert, non-porous, and resistant to most cleaning agents**, making it easy to clean and sterilize (e.g., autoclaving or soaking in strong detergents). Unlike plastic, it does not absorb residues or harbor microbial growth.

7. **Long Lifespan** Properly maintained, borosilicate glassware can last **decades**, making it a cost-effective investment compared to disposable plastic alternatives.

8. **Compatibility with Vacuum Systems** The **STJ joint** allows for sealing with rubber stoppers or ground glass adapters, enabling use in **vacuum filtration, distillation, or other low-pressure applications**.

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1. **Fragility Compared to Plastic** While borosilicate glass is tougher than soda-lime glass, it can still **shatter if dropped or subjected to sudden temperature changes** (e.g., placing a hot flask in cold water). Care must be taken during handling.

2. **Weight** Glass is **heavier than plastic alternatives**, which can make handling cumbersome, especially for large volumes or when working with multiple flasks simultaneously.

3. **Cost** More expensive than **disposable plastic flasks** or basic soda-lime glassware. However, the long-term durability often justifies the initial investment in a laboratory setting.

4. **Maintenance Requirements** Unlike plastic, glass requires **regular cleaning** to prevent residue buildup, which can affect accuracy in measurements or reactions. Scratches or pitting from abrasive cleaners can also weaken the glass over time.

5. **Limited Flexibility in Modifications** Unlike plastic, glass cannot be easily **cut, bent, or modified** without specialized tools and expertise. Any repairs (e.g., sealing cracks) typically require professional glassblowing services.

6. **Potential for Contamination** If not cleaned properly, **glassware can harbor microbial biofilms or chemical residues**, which may interfere with experiments. Unlike plastic, glass does not leach additives, but it can absorb organic compounds if not cleaned thoroughly.

7. **Storage Space** Glassware takes up **more storage space** than plastic due to its bulkiness and weight, requiring careful organization in a lab.

8. **Potential for Joint Leaks** The **STJ joint** must be sealed properly with a **rubber stopper or grease** to prevent leaks during vacuum or reflux operations. Improper sealing can lead to contamination or loss of reactants.

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The **Chemglass 33985-1L VWR Pyrex Erlenmeyer Flask (40/35 STJ)** is a **high-quality, versatile, and durable** piece of laboratory glassware that excels in applications requiring **chemical resistance, heat tolerance, and precision**. Its **standardized joint** ensures compatibility with other glassware, while its **borosilicate construction** provides reliability for demanding experiments. However, its **fragility, weight, and higher cost** compared to disposable alternatives must be considered, particularly in settings where **convenience or budget constraints** are priorities.

For **academic, industrial, or analytical laboratories** where **accuracy, durability, and chemical compatibility** are critical, this flask is an **excellent long-term investment**. In contrast, **small-scale or disposable-focused labs** may find it overkill and opt for cheaper plastic alternatives instead.

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- You require **high durability, chemical resistance, and heat tolerance** for routine or advanced laboratory work.

- You need **standardized glassware** that fits seamlessly into existing setups (e.g., reflux, distillation, or titration systems).

- You prioritize **long-term reliability** over disposability and are willing to invest in quality glassware.

- Your lab frequently handles **aggressive chemicals, high temperatures, or vacuum operations**.

- You work in a **budget-conscious or low-volume setting** where disposable plastic flasks are sufficient.

- You frequently **drop or mishandle glassware**, as the risk of breakage may outweigh the benefits.

- You need **flexibility in modifications** (e.g., cutting or reshaping the flask), as glass requires specialized tools for repairs.

- Your experiments involve **biological samples** where **sterilization concerns** (e.g., endotoxin contamination) are a major issue (though Pyrex is generally safer than some plastics).

**Final Verdict:** For most **serious laboratory applications**, this flask is a **strong recommendation** due to its **superior performance and longevity**. However, weigh the pros and cons against your specific workflow before purchasing.

Details:

VWR Pyrex 33985-1L Erlenmeyer Flask 40/35 Male STJ 1000 ml.

specifications plasticwarelabsuppy:

• brand: Chemglass
• mpn: 33985-1l
• unit type: Unit
• country of origin: United States
• intended use/discipline: Biological Laboratory, Dental Laboratory, Medical Laboratory, Microbiological Laboratory, Physical Laboratory

seller plasticwarelabsuppy:

• city: Ponder, Texas
• # reviews: 2186
• rating: 100.0%

offer plasticwarelabsuppy:

• availability: In Stock
• sold: 0
• options: Ship-to-home
• quantity: 1
• best offers: True
• started: March 3, 2026

payments plasticwarelabsuppy:

• credit card: Mastercard
• other
• wallet: Google-pay

shipping plasticwarelabsuppy:

• cost: $0.00
• class: Standard, Expedited
• service: USPS Ground Advantage, Expedited
• transit: 3-7 Days
• carrier: USPS
• type: Fixed

general plasticwarelabsuppy:

• condition: Used
• Medical, Lab Dental Supplies > Glassware Plasticware > Other Medical Lab Glassware

returns plasticwarelabsuppy:

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

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