Helpful glass facts
Glass Properties
|
Properties |
Borosilicate |
Quartz |
| Coefficient of expansion ( x 10-7 cm/cm/°C) |
32.5 | 8.0 |
| Temperature limits |
230°C (Normal use) |
1000°C |
| Softening Point | 821°C | 1580°C |
|
Refractive index |
1.474 | 1.458 |
How to identify if an unknown glass is borosilicate glass, without leaving the Lab!
- Borosilicate glass can be readily identified by its’ refractive index, 1.474
- By immersing the glass in a container of a liquid of similar refractive index, the glass will disappear.
- Such liquids are:
- Mineral oil,
- Dry benzene-methanol mixture, 84:16 (v/v) at room temperature,
- Anhydrous gylcerol
How to identify if an o-ring is viton.
Viton floats in perchloroethylene, if it sinks, it’s not Viton.
Glass Filter Designations
| Porosity | Microns |
| Fine F | 4-5.5 |
| Medium M | 10-15 |
| Coarse C | 40-60 |
| Extra Coarse XC | 170-220 |