题目内容

【题目】某化学实验小组同学利用以下实验装置制取氨气，并探究氨气的性质(部分仪器已略去)。请回答：

(1)实验室制备氨气的化学方程式为______________________。

(2)用装置B收集氨气时，应选择氨气的进气口是________(填“a”或“b”)，并说明选择的理由是________________________________。

(3)打开装置B中的止水夹c，若观察到烧瓶内产生了红色喷泉，则说明氨气具有的性质是________________、________________。

(4)为防止环境污染，以下装置(盛放的液体均为水)可用于吸收多余氨气的是________(填序号)。

【答案】(1)2NH4Cl+Ca(OH)2CaCl2+2NH3↑+2H2O

(2)a 氨气密度比空气密度小

(3)极易溶于水，与水反应生成碱

(4)②④

【解析】(1)实验室制取氨气的方程式为2NH4Cl+Ca(OH)2CaCl2+2NH3↑+2H2O。

(2)氨气比空气的密度小，可用向下排空气法收集，导气管要伸入烧瓶底部。

(3)能形成喷泉，证明氨气极易溶于水，酚酞变红，说明氨气的水溶液显碱性。

(4)①不利于氨气的吸收，②、④能防止倒吸，③易发生倒吸。

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删除：把多余的词用斜线（\）划掉。

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