Answer
a) $Ca(OH)_2+2HCL$ -> $CaCl_2 + H_2O$
b) $Fe_2O_3+3H_2$ -> $2Fe + 3H_2O$
c) $NaHCO_3 + H_2SO_4$ -> $Na_2SO_4 + CO_2 + H_2O$
d) $2C_2H_6 + 7)_2$ -> $4CO_2 + 6H_2O$
Work Step by Step
a) Ca(OH)2+2HCL -> CaCl2+H2O
b) Fe2O3+3H2 -> 2Fe+3H2O
c) NaHCO3+H2SO4 -> Na2SO4+CO2+H2O
d) 2C2H6+7)2 -> 4CO2+6H2O