$6 \times 10^{-3}$ mole $K_2Cr_2O_7$ reacts completely with $9 \times 10^{-3}$ mole $X^{n+}$ to give $XO_3^-$ and $Cr^{3+}$. The value of $n$ is

What is the value of $x$ and $y$ in order to balance the following redox reaction?
$x CuO + y NH_3 \longrightarrow x Cu + N_2 + x H_2 O$

The reaction,$K_2Cr_2O_7 + m \, FeSO_4 + n \, H_2SO_4 \longrightarrow Cr_2(SO_4)_3 + p \, Fe_2(SO_4)_3 + K_2SO_4 + q \, H_2O$ when balanced,$m, n, p$ and $q$ are,respectively:

The volume of $0.02 \ M$ acidified acidified permanganate solution required for complete reaction of $60 \ mL$ of $0.01 \ M \ I^{-}$ ion solution to form $I_2$ in $mL$ is

Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$K_2Cr_2O_7 \xrightarrow{\Delta } K_2CrO_4 + Cr_2O_3 + O_2 \uparrow$

Consider a titration of potassium dichromate solution with acidified Mohr's salt solution using diphenylamine as indicator. The number of moles of Mohr's salt required per mole of dichromate is