Error:
FeSO4 %2B CrO3 %2B H2SO4 %3D Fe2%28SO4%293 %2B Cr2%28SO4%293 %2B H2O
^
Unexpected character ('%')FeSO4 %2B CrO3 %2B H2SO4 %3D Fe2%28SO4%293 %2B Cr2%28SO4%293 %2B H2O
^
Unexpected character ('%')