b. Distillation apparatus: The entire assembly (Figure 19) consists of a kjeldahl flask, an efficient bulb or trap, and a vertical condenser. Connections between these units can be made with short lengths of rubber tubing. Although gas-heated distillation apparatus may be used, electrically heated units often offer smoother operation and less bumping. The entire apparatus should be steamed out before use, by distilling 500 ml of distilled water (low in ammonia) until the distillate becomes free of ammonia.