Error:
H2SO4 %2B NH3 %2B K2FeO4 %3D H2O %2B K2SO4 %2B N2 %2B Fe2%28SO4%293
^
Unexpected character ('%')H2SO4 %2B NH3 %2B K2FeO4 %3D H2O %2B K2SO4 %2B N2 %2B Fe2%28SO4%293
^
Unexpected character ('%')