【单选题】【消耗次数：1】
砷盐检查法中碘化钾和氯化亚锡的主要作用是
①
将As5+还原为As3+
②
将As3+氧化为As5+
③
加快氢气的产生
④
排除硫化物的干扰
⑤
反应更彻底
参考答案：
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相关题目
【多选题】
砷盐检查法中，关于醋酸铅棉花的应用，正确的是
①
控制反应温度
②
形成稳定的砷斑
③
吸收除去硫化氢气体
④
装管高度6--8
⑤
m
⑥
大约需要60mg醋酸铅棉花
【多选题】
关于古蔡氏法检查砷盐的叙述，正确的有
①
反应生成的砷化氢遇溴化银试纸，产生黄色至棕色的砷斑
②
加碘化钾使五价的砷还原成三价砷
③
金属锌和酸作用生成新生态的氢
④
氯化亚锡可防止碘还原成碘离子
⑤
在反应中氯化亚锡不会和锌发生反应
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①
why
②
that
③
whether
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when
【单选题】
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insist
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keep
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preserve
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kill
【单选题】
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gave
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declared
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promised
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assured
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inside
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inner
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in
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within
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To show the authors grandparents were honest.
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To explain what Integrity Triad realy embodies.
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To demonstrate the authors grandparents motto
【单选题】
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disapproval
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distaste
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dissatisfaction
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dismay
【单选题】
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preserve
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sell
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save
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. buy