Error:
H2SO4 %2B KMnO4 %2B Fe %3D Fe2%28SO4%293 %2B MnSO4 %2B K2SO4 %2B H2O
^
Unexpected character ('%')H2SO4 %2B KMnO4 %2B Fe %3D Fe2%28SO4%293 %2B MnSO4 %2B K2SO4 %2B H2O
^
Unexpected character ('%')