Azotning oksidlanish darajasi +2 ga qaytarilganlarini tanlang. 1) HN03

73. (v6-104-9) Azotning oksidlanish darajasi +2 ga qaytarilganlarini tanlang. 1) HN03 + Ag = AgN03 + N02 + H20; 2) HN03 + HCI + Au = H[AuCI4] + NO + H20; 3) HN03 + CuS = CuS04 + N02 + H20; 4) HN03 + CaC03 = Ca(N03)2 + C02 + H20; 5) HN03 + P = H3P04 + N02 + H20; 6) HN03 + HCI + Pt = H2[PtCI6] + NO + H20; 7) HN03 + Cu = Cu(N03)2 + N02 + H20. A) 1,4 B)1,3, 5,7 C)2, 3, 5, 7
D) 2, 6