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关于Na_2O_2与H_2O反应的实验,为什么教材中只要求检验生成的气体是否为氧气,却不要求检验化学反应中另一生成物——NaOH呢?如能用酸碱指示剂检验出反应后的溶液显碱性,从而推出另一生成物是NaOH不是更有利于教学吗?带着这个问题,我们进行了如下探讨。首先,我们观察了Na_2O_2和H_2O在试管中反应的实验现象。发现二者反应并不象其它固体物质与溶液反应放出气体的现象那样——固体消失后,产生的气泡很快消失,而是固体Na_2O_2消失后,产生的气泡还要持续很长时间,且随着时间的延长气泡慢慢减少,如检
Regarding the experiments on the reaction of Na 2 O 2 with H 2 O, why does the textbook only require to check whether the generated gas is oxygen, but it is not required to check NaOH, another product of the chemical reaction? If the solution after the reaction can be tested with an acid-base indicator Alkaline, so that the introduction of another product is NaOH is not more conducive to teaching? With this issue, we conducted the following discussion. First, we observed the experimental phenomenon of Na 2 O 2 and H 2 O in the test tube. It was found that the reaction between the two is not like the reaction of other solid matter and solution to release gas. After the solid disappears, the bubbles produced disappear quickly. However, after the solid Na 2 O 2 disappears, the generated bubbles still last for a long time. With the extension of time, the bubbles slowly decrease, such as