Ca -> CaO -> Ca(OH)2 -> CaCl2 -> Ca(OH2) -> Ca(NO3)2
2Ca+O2=2CaO (нагревание) СaO+H2O=Ca(OH)2 Ca(OH)2+2HCl=CaCl2+2H2O CaCl2+2NaOH=Ca(OH)2↓+2NaCl Ca(OH)2+2HNO3=Ca(NO3)2+2H2O