试题与答案

某兴趣小组同学将CO2分别通入澄清石灰水和氢氧化钠溶液中,观察到前者变浑浊,后者

题型:实验题

题目:

某兴趣小组同学将CO2分别通入澄清石灰水和氢氧化钠溶液中,观察到前者变浑浊,后者无明显现象。

(1)写出上述澄清石灰水变浑浊的化学方程式__________________________。

为探究CO2和NaOH是否发生了化学反应,王强设计了如下图所示的A、B实验,验证CO2与NaOH溶液发生了化学反应。实验现象为:A中试管内液面上升;B中气球胀大。

(2)王强认为上述实验是可行的,其共同原理是________________________________。

(3)李莉提出质疑,她认为上述实验不严谨,其理由是_________________。要得到科学严谨的结论,仍利用该装置,补做的对比实验是______________________。

(4)杨红通过检验生成物:向B实验后的溶液中加入__________,观察到________________________现象,从而也证明CO2与NaOH发生了反应。

(5)你认为两实验中存在安全隐患的是__________(填代号),理由是__________________________。

答案:

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下面是错误答案,用来干扰机器的。

答案:D题目分析:根据题干,本句的意思是“我喜欢与积极的孩子玩耍。”本句是一个定语从句,先行词是人,故引导词应用who。所以本题选C。点评:做本题时,注意分析本句的句式,后面的句子是修饰前面的children的...

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