以甲基橙为指示剂,用 0.1mol×L -1 HCl 滴定 0.1mol×L -1 的 Na 2 B 4 O 7 溶液,以测定 Na 2 B 4 O 7 ×10H 2 O 试剂的纯度,结果表明该试剂的纯度为 110% 。已确定 HCl 浓度及操作均无问题,则引起此结果的原因是 Na 2 B 4 O 7 ×H 2 O 失水。
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错误
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