The distillation flask is made of 3.3 high borosilicate glass, 250 mL standard grinding mouth 19/26, round bottom with side neck, and can be directly heated. The thickness of the bottle wall is uniform, the temperature resistance is 200 ℃, the scale is ± 5%, and the side neck forms a 45 ° angle for easy connection to the condenser tube. Equipped with anti scald silicone sheath, providing drop cushioning. Students can use it for ethanol water separation and essential oil extraction, which is safe and intuitive, suitable for middle school chemistry "substance separation" experimental teaching, and helps students understand the principle of "separating mixtures using boiling point differences".