Question

When $MnO_2$ is fused with $KOH$ and $KNO_3$, a coloured compound is formed. Choose the right compound with the appropriate colour

• A. $K_2MnO_4$, green
• B. $KMnO_4$, purple
• C. $Mn_2O_3$, brown
• D. $Mn_3O_4$, black

Answer 1

Answer: (A)

$K_2MnO_4$, green

Answer 2

When $MnO _{2}$ react with fused mixture of $KOH$ and $KNO _{3}$. it gives $K _{2} MnO _{4}$ (green) as follows

$MnO _{2}+ KNO _{3}+2 KOH {->[{\Delta}]}\underset{(\text { green })}{ K _{2} MnO _{4}}+ KNO _{2}+ H _{2} O$