When a mixture of potassium dichromate and potassium chloride is heated with concentrated $H_2SO_4$,which of the following is produced as red vapors?

The oxidation states of transition metal atoms in $K_{2}Cr_{2}O_{7}$,$KMnO_{4}$ and $K_{2}FeO_{4}$,respectively,are $x$,$y$ and $z$. The sum of $x$,$y$ and $z$ is

If the magnetic moment $(\mu)$ of an oxide of manganese is $4.9 \ BM$,which oxide is it?

$A$ purple colored compound of Manganese $(X)$ decomposes on heating to liberate oxygen and forms compounds of Manganese $(Y)$ and $(Z)$. Compound $(Z)$ reacts with $KOH$ in the presence of potassium nitrate to give compound $(Y)$. Compounds $(X)$,$(Y)$,and $(Z)$ respectively are:

What is the oxidation state of osmium in $7B$ and $7C$,respectively?

Which of the following ores is used for the production of $K_2Cr_2O_7$?