【多选题】【消耗次数：1】
下列操作中哪些是错误的
①
手捏比色皿毛面
②
采用分光光度法测定水中铁含量时，必须采用石英比色皿
③
测定多种浓度溶液吸光度时，由低浓度至高浓度顺序测定
④
可见、紫外分光光度计开机后马上就进行测量
参考答案：
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相关题目
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在分光光度计上用标准对照法测定某中药注射液中黄酮甙的含量，标准溶液浓度为0.02mg/ml，其吸光度为0.460，样品供试液吸光度为0.230，样品中黄酮甙含量为
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