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用铬酸洗液清洗碱式滴定管时,首先将其最下端的玻璃尖咀卸掉,然后将滴定管倒立,使上口插入盛有铬酸洗液(30gK_2Cr_2O_7+30ml热水+ 300ml浓H_2SO_4)的烧杯或锥形瓶中,并固定在滴定台的夹子上,接着象滴定操作时一样,左手的拇指与食指挤压乳胶管中的玻璃珠,与此同时,右手拿着洗耳球尖咀对准乳胶管口,右手再轻轻放松洗耳球,这时,随着滴定管内空气的抽出,洗液将由滴定管中缓缓上升.如果一次不能吸满,则先松开左手,后移开洗耳球,排出空气后
Cleaning the burette with a chromic acid wash solution, first remove the glass tip of the lowest end of the burette, and then the burette upside down, so that the upper mouth inserted chromic acid wash solution (30gK_2Cr_2O_7 + 30ml hot water + 300ml concentrated H_2SO_4) Beaker or conical flask, and fixed to the titration station clamp, then the same as the titration operation, the left thumb and forefinger squeeze the glass bead in the latex tube, at the same time, Quasi latex mouth, right hand and then gently relax the ear wash ball, then, with the burette air extraction, lotion will slowly rise from the burette.If you can not suck full, then first open the left hand, Ear ball, after the air is discharged