Question

For decolourisation of 1 mole of kmno4, the moles of h2o2 required is

Answer 1

The balance chemical equation for the reaction of $\mathrm{KMnO}_{4}$ with $\mathrm{H}_{2} \mathrm{O}_{2}$ can be written as:

$3 \mathrm{H}_{2} \mathrm{O}_{2}+2 \mathrm{KMnO}_{4} \rightarrow 3 \mathrm{O}_{2}+2 \mathrm{MnO}_{2}+2 \mathrm{KOH}+2 \mathrm{H}_{2} \mathrm{O}$

Here 5 moles of $\mathrm{H}_{2} \mathrm{O}_{2}$ react with 2 moles of $\mathrm{KMnO}_{4}$. Hence for 1 mole of $\mathrm{KMnO}_{4}$, we need 2= 2.5 moles of $\mathrm{H}_{2} \mathrm{O}_{2}$ molecules.  

The balance chemical equation for 1 mole of $\mathrm{KMnO}_{4}$ can be shown as:

$\frac{3}{2} \mathrm{H}_{2} \mathrm{O}_{2}+\mathrm{KMnO}_{4} \rightarrow \frac{5}{2} \mathrm{O}_{2}+\mathrm{MnO}_{2}+\mathrm{KOH}+\mathrm{H}_{2} \mathrm{O}$

Hence, $\frac{2}{5}\ moles\ of\ \mathrm{H}_{2} \mathrm{O}_{2}$ are required for one mole of $\mathrm{KMnO}_{4}$.

Answer 2

Answer: 5/2 is the correct answer