Which one is the oxidising agent in the reaction below?
$2CrO_4^{2-} + 2H^{+} \to Cr_2O_7^{2-} + H_2O$

What is the equivalent weight of potassium permanganate $(KMnO_4)$ when it acts as an oxidizing agent in the conversion of ferrous ions to ferric ions in an acidic medium?

In chloro-alkali industries,during the Solvay ammonia process,a redox change occurs during:

In neutral or faintly alkaline medium,$MnO_4^{-}$ oxidizes $I^{-}$ to iodate. What is the volume (in $L$) of $0.02 \ M \ KMnO_4$ required to completely convert $1 \ L$ of $0.5 \ M \ KI$ solution to iodate in neutral or faintly alkaline medium?

$15 \ mL$ of aqueous solution of $Fe^{2+}$ in acidic medium completely reacted with $20 \ mL$ of $0.03 \ M$ aqueous $Cr_{2}O_{7}^{2-}$. The molarity of the $Fe^{2+}$ solution is ........... $\times 10^{-2} \ M$ (Round off to the Nearest Integer).

Identify the substance oxidised,reduced,oxidising agent,and reducing agent for each of the following reactions:
$(a)$ $2 AgBr_{(s)} + C_6 H_6 O_{2(aq)} \rightarrow 2 Ag_{(s)} + 2 HBr_{(aq)} + C_6 H_4 O_{2(aq)}$
$(b)$ $HCHO_{(l)} + 2 [Ag(NH_3)_2]^+_{(aq)} + 3 OH^-_{(aq)}$ $\rightarrow 2 Ag_{(s)} + HCOO^-_{(aq)} + 4 NH_{3(aq)} + 2 H_2 O_{(l)}$
$(c)$ $HCHO_{(l)} + 2 Cu^{2+}_{(aq)} + 5 OH^-_{(aq)} \rightarrow Cu_2 O_{(s)} + HCOO^-_{(aq)} + 3 H_2 O_{(l)}$
$(d)$ $N_2 H_{4(l)} + 2 H_2 O_{2(l)} \rightarrow N_{2(g)} + 4 H_2 O_{(l)}$
$(e)$ $Pb_{(s)} + PbO_{2(s)} + 2 H_2 SO_{4(aq)} \rightarrow 2 PbSO_{4(s)} + 2 H_2 O_{(l)}$