Question

Ca -> CaO -> Ca(OH)2 -> CaCl2 -> Ca(OH2) -> Ca(NO3)2

Answer 1

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