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linhmap672
2 năm trước
Câu 1.Dãy chất nào sau đây đều là oxit (axit, bazơ, muối):A. HCl, H3PO4, H2SO4.B.CuSO4, Na2CO3, NaCl.C. CuO, SO2, P2O5.D.NaOH, Ca(OH)2, Cu(OH)2
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