Merck, CLS4620125-24EA, Pyrex®distilling flask

The Corning PYREX distilling flask is a 125 mL borosilicate-glass round-bottom vessel with a sidearm for small-scale laboratory distillation assemblies. Its glass construction supports observation of the liquid phase during heating and is appropriate for conventional laboratory distillation setups when fitted with suitable joints, tubing, and support hardware. The 125 mL format is supplied as 24 flasks per case, arranged as packs of six, and is nonsterile. The flask is designed for connection to a condenser through its sidearm and for fitting a suitable thermometer or stopper at the neck. Secure the vessel with appropriate glassware clamps, avoid direct thermal shock, and do not use a closed distillation system without pressure relief. Select heating methods and receiver configuration based on the solvent's volatility and hazard profile. The flask is not a volumetric flask, vacuum-rated pressure vessel, or sterile container.