1) Fe2(SO4)+NAOH=FEOH+6NA2SO4 3FE+3SO4+2NA+OH=FEOH+2NA+6SO4 3FE+OH=FEOH 2)K2SO4+HCL=KCL+HCO3 K+SO4+H+CL=CO+K+CL+H SO4=CO3 3)CAI2+Pb(NO3)2=CA(NO3)2+PbI CA+I+2Pb+2NO3=3CA+2NO3+PbI Pb+I=PbI