【多选题】【消耗次数：1】
区别6，7-呋喃香豆素和7，8-呋喃香豆素时，可将它们分别加碱水解后再采用
①
异羟肟酸铁反应
②
Gibb′s反应
③
Emerson反应
④
三氯化铁反应
⑤
醋酐-浓硫酸反应
参考答案：
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