一、防装置漏气装置连接好后必须检验气密性 ,避免因装置漏气而长时间收集不到氧气。二、防试管破裂盛有药品的试管固定在铁架台上时 ,应使试管口略向下倾斜 ,防止药品中蒸发出的水分凝结为液态水倒流引起试管破裂 ;加热时要先来回移动酒精灯使试管受热均匀 ,避免因局部受热温 First, the air leakage prevention device must be tested after the connection is good airtight, to avoid leakage of the device for a long time can not collect oxygen. Second, the anti-tube rupture test tube filled with drugs fixed on the iron stand, should make the test tube mouth slightly downward, to prevent condensation of liquid water in the drug to condense liquid water back to cause the test tube rupture; to move the alcohol lamp back and forth when heating Heat the test tube evenly to avoid local heating