$NaCl$ reacts with conc. $H_2SO_4$ and $K_2Cr_2O_7$ to give reddish fumes $(B)$,which react with $NaOH$ to give yellow solution $(C)$. $(B)$ and $(C)$ respectively are:

Misch metal is an alloy of:

The highest oxidation state of $Mn$ is exhibited in $Mn_2O_7$. The correct statements about $Mn_2O_7$ are:
$(A)$ $Mn$ is tetrahedrally surrounded by oxygen atoms.
$(B)$ $Mn$ is octahedrally surrounded by oxygen atoms.
$(C)$ Contains $Mn-O-Mn$ bridge.
$(D)$ Contains $Mn-Mn$ bond.
Choose the correct answer from the options given below:

Which one of the following,when dissolved in water,gives a coloured solution in a nitrogen atmosphere?

The color of acidified $K_2Cr_2O_7$ is not changed by:

For $Cu_{2}Cl_{2}$ and $CuCl_{2}$ in aqueous medium,which of the following statements is correct?