题目

小明同学往氢氧化钠溶液中滴加稀盐酸研究中和反应时,忘记了滴加酸碱指示剂。为了确认滴加的盐酸是否已经过量,从烧杯中取少量反应后的溶液于试管中,用某种试剂进行检验。下表是小明同学设计的实验方案,其中不正确的是实验方案使用的试剂判断的方法 A铁粉如果有气泡产生,表明盐酸已经过量 BpH试纸如果pH<7,表明盐酸已经过量 C硝酸银溶液如果有白色沉淀产生,表明盐酸已经过量 D紫色石蕊试剂如果溶液变成红色,表明盐酸已经过量根据下列句子及所给汉语注释,写出空缺处各单词的正确形式。每空只写一词。 1.My father was born in        (五月). 2.They are        (意识到的)of the dangers. 3.People        (呼吸)more slowly when they are asleep. 4.A meeting was        (举行)to discuss our future. 5.Children learn        (礼貌)by watching their parents. 6.You shouldn’t leave a child        (单独)in the house. 7.Even though Jenna was speeding,the police let her go with a        (警告). 8.They are        (建造)a new bridge over the river. 9.Why do you think you did so        (糟糕地)in your test? 10.She looks        (熟悉的)to me,but I don’t remember her name.
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