Question

What happen if I want to determine glucose in urine by kmno4 and then no glucose have been found in urine
So what's the result of equation including the color?

Answer 1

The purple pink solution of potassium permanganate (MnO4-) is reduced by glucose (C6H12O6) in acidic conditions to a colorless solution of manganese ions (Mn2+). The time taken for the color to be lost is directly proportional to the concentration of glucose :
5C6H12O6 + 24KMnO4 + 36H2SO4  30CO2 + 24MnSO4 + 12K2SO4 + 66H2O
MnO4- + 8H+ + 5e-  Mn2+ + 4H2O
Under normal conditions, there is no glucose or any other sugar in the urine. Sugars appear only in cases of pancreas or kidney disease. So if there is no glucose have been found in urine, potassium permanganate will retain a purple pink color i.e. analytical reaction of glucose oxidation will not proceed.

Answer: purple pink solution (MnO4-)