Classification: Flask
250ml round bottom Nitrogen flasks with PTFE stopcock
The conical flask with clear scale mark is for easy estimation of liquid volume,transparent material, easy to observe internal reaction condition.
Made of borosilicate glass, with good physical strength,sturdy and durable.It has a glass stopper that prevents liquid from evaporating.
1. Borosilicate glass
It is a special glass material with low expansion rate, high temperature resistance, high strength, high hardness, high transmittance and high chemical stability
2. APPROX scale
The beaker in the situation of room temperature or heating, it is easy to make scale fuzzy and inconvenient to experiment. But the APPROX scale is more accurate and durable, and it is not easy to scratche
3. Label
We have convenient ,practical label on our products surface
Borosilicate Glass Boro 3.3
Nitrogen flasks, round bottom (Schlenk Flasks) with PTFE stopcock,250ml
| SiO2 Content | >80% |
| Strain Point | 520℃ |
| Annealing Point | 560℃ |
| Softening Point | 820℃ |
| Refractive Index | 1.47 |
| Light Transmission (2mm) | 0.92 |
| Elastic Modulus | 67KNmm-2 |
| Tensile Strength | 40-120Nmm-2 |
| Glass Stress Optical Coefficient | 3.8*10-6mm2/N |
| Processing Temperature (104 dpas) | 1220℃ |
| Linear Coefficient of Expansion (20-300℃) | 3.3*10-6K-1 |
| Density (20℃) | 2.23gcm-1 |
| Specific Heat | 0.9jg-1K-1 |
| Thermal Conductivity | 1.2Wm-1K-1 |
| Hydrolytic Resistance (ISO 719) | Grade-1 |
| Acid Resistance (ISO 195) | Grade-1 |
| Alkali Resistance (ISO 695) | Grade-1 |
| Thermal Shock Resistance Rod 6*30mm | 300℃ |
