$A$ negative $e.m.f.$ for a cell represents:

Impure copper containing $Fe$,$Au$,and $Ag$ as impurities is electrolytically refined. $A$ current of $140 \ A$ for $482.5 \ s$ decreased the mass of the anode by $22.26 \ g$ and increased the mass of the cathode by $22.011 \ g$. The percentage of iron in the impure copper is (Given molar mass $Fe = 55.5 \ g \ mol^{-1}$,molar mass $Cu = 63.54 \ g \ mol^{-1}$)

Which one of the following graphs between molar conductivity $\left(\Lambda_m\right)$ versus $\sqrt{C}$ is correct?

Based on the following information,arrange four metals,$A$,$B$,$C$,and $D$,in order of increasing ability to act as reducing agents:
$(I)$ Only $C$ reacts with $1 \ M \ HCl$ to give $H_{2(g)}$.
$(II)$ When $A$ is added to a solution of the other metal salts,metallic $D$ is formed,but not $B$ or $C$.

Why is electrochemistry important for the invention of the latest technology?

Calculate the equilibrium constant for the reaction: $Cl_{2(g)} + 2I^{-}_{(aq)} \to 2Cl^{-}_{(aq)} + I_{2(s)}$
Given: $E^o_{(Cl_2|2Cl^{-})} = 1.36 \ V$ and $E^o_{(I_2|2I^{-})} = 0.536 \ V$.