Question

Ca-->Ca(OH)2-->CaCO3-->CaO-->CaSO4-->CaCl2-->Ca(OH)2

Answer 1

1) Ca +2H2O = Ca(OH)2 + H2

2) CaOH2+CO2 = CaCO3+H2O

3)CaCO3 =t= CaO + CO2 

4) CaO +H2SO4 = CaSO4(осадок) + H2O

5) CaSO4+4СО =700-800 град С= CaS +4СО2

CaS+2HCl(разб)=CaCl2+H2S

6) CaCl2 + 2NaOH = Ca(OH)2 + 2NaCl