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已知：Cu 2 O是红色固体，能与稀硫酸发生反应：Cu 2 O+H 2 SO 4 =CuSO 4 +Cu+H 2 O有同学认为在实验室做用氢气还原CuO的实验时得到的红色固体中可能混有Cu 2 O．请设计实验检验红色固体中是否混有Cu 2 O．简要说明实验过程、现象和结论．
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