The chromium(III) species reacts with hydrogen peroxide in aqueous solution to form the chromate ion:

Question

2CrO2- 3 H2O2 2OH- 2CrO42- 4H2O

If the chromate ion is produced at an instantaneous rate of 0.0087 mol/L/s at a particular temperature, what is the rate of reaction?

Answer 1

appearance of CrO4)-2 @  0.0087 mol/L/s is an acceptable rate

& @  2CrO2- & 3 H2O2 &  2OH--->  2CrO42-  & 4H2O so are:

the appearance of H2O @ twice (CrO4)-2  =   0.0174 mol/L/s

the disappearance of CrO2)-   equalling CrO4)-2  =   0.0087 mol/L/s

the disappearance of OH)-  equalling CrO4)-2  =   0.0087 mol/L/s

the disappearance of H2O2  equalling  3/2 (CrO4)-2  =   0.0130 mol/L/s