When potassium permanganate $(KMnO_4)$ is heated at $513 \ K$,it decomposes to form two manganese-based products. The physical properties of the product in which manganese has a higher oxidation state than the other are:

The total number of $Mn=O$ bonds in $Mn_2O_7$ is

What is the composition of the alloy that exhibits the property of shape memory?

$A$ violet compound of manganese $(A)$ decomposes on heating to liberate oxygen and compounds $(B)$ and $(C)$ of manganese are formed. Compound $(C)$ reacts with $KOH$ in the presence of potassium nitrate to give compound $(B)$. On heating compound $(C)$ with conc. $H_{2}SO_{4}$ and $NaCl$,chlorine gas is liberated and a compound $(D)$ of manganese along with other products is formed. Identify compounds $A$ to $D$ and also explain the reactions involved.

Misch metal is an alloy of:

The incorrect statement is: