Question

c→co → ch4 → co 2 → ca co3 → ca o→ ca ( oh ) 2 → ( ca oh ) 2 so4→ ca so4

Answer 1

2C+O2=2O
  CO+ 3H2 = CH4+ H2O
CH4+2O2= CO2+2H2O
 CO2+ CaO= CaCO3
CaCO3 = CaO+CO2
CaO+H2O= Ca(OH)2
Ca(OH)2+CaSO4= CaOH)2SO4
CaOH)2SO4 +H2SO4=2CaSO4+2H2O