Error:
K2Cr2O7 %2B SO2 %2B H2SO4 %3D KCr%28SO4%292 %2B H2O
^
Unexpected character ('%')K2Cr2O7 %2B SO2 %2B H2SO4 %3D KCr%28SO4%292 %2B H2O
^
Unexpected character ('%')