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高一化学第一册(必修)(2003年6月第1版)P19实验1—4氢氧化钡晶体与氯化铵晶体反应中的能量变化原实验方案存在的缺陷:从教材的编排来看,做该实验时,本地还处在较热的时节,水沾在烧杯底的玻璃片上难以冻结,在班上演示可见性较差;同时,药品用量过大,混合过程中及在烧杯中搅拌时氨味很浓,污染大,对师生造成危害。改进办法:用装过加碘盐的塑料袋(或用其它结实些的塑料袋,以防搓破)代替烧杯,称取2.5g 氯化铵晶体倒入塑料袋中,从中间系扎。再称5g 粉末状氢氧化钡晶
Higher Chemistry First Book (compulsory) (June 2003, first edition) P19 Experiment 1-4 Energy changes in the reaction between barium hydroxide crystals and ammonium chloride crystals Defects in the original protocol: From the point of arrangement , When doing the experiment, the locality is still in the hot season, the water sticks on the glass bottom of the beaker is difficult to freeze, demonstrating the poor visibility in the class; meanwhile, the dosage of the drug is too large, the mixing process and stirring in the beaker When the ammonia smell is very strong, polluting, causing harm to teachers and students. Methods to improve: with over-iodized salt plastic bags (or other solid plastic bags to prevent rubbing broken) instead of beaker, weighing 2.5g ammonium chloride crystals into the plastic bag, tie from the middle. 5g powdered barium hydroxide again said