Level 1

When a lead storage battery is discharged:

The values of the limiting molar conductivity $\left(\mathrm{\Lambda }°\right)$ for $\mathrm{NaCl}, \mathrm{HCl}$ and $\mathrm{NaOAc}$ are $126.4, 425.9$ and $91.0 \mathrm{S} {\mathrm{cm}}^2 {\mathrm{mol}}^{-1}$, respectively. For $\mathrm{HOAc}.$ $\mathrm{\Lambda }°$ in $\mathrm{S} {\mathrm{cm}}^2 \mathrm{mol}{ }^{-1}$ is

Among the following metals, the strongest reducing agent is:

Consider the cell potentials ${\mathrm{E}}_{{\mathrm{Mg}}^{2+}\mid \mathrm{Mg}}^{\circ }=-2.37 \mathrm{V}$ and ${\mathrm{E}}_{{\mathrm{Fe}}^{3+}\mid \mathrm{Fe}}^{\circ }=-0.04 \mathrm{V}$. The best reducing agent would be

The position of some metals in the electrochemical series in decreasing electropositive character is given as $\mathrm{Mg}>\mathrm{Al}>\mathrm{Zn}>\mathrm{Cu}>\mathrm{Ag}$. What will happen if a copper spoon is used to stir a solution of aluminium nitrate?

Electrode potential data are given below.

${\mathrm{Fe}}^{3+}\left(\mathrm{aqueous}\right)+{\mathrm{e}}^{-}⟶{\mathrm{Fe}}^{2+}\left(\mathrm{aq}\right); {\mathrm{E}}^{\circ }=+0.77$

${\mathrm{Al}}^{3+}\left(\mathrm{aqueous}\right)+3{\mathrm{e}}^{-}⟶\mathrm{Al}\left(\mathrm{s}\right); {\mathrm{E}}^{\circ }=-1.66 \mathrm{V}$

${\mathrm{Br}}_2\left(\mathrm{aqueous}\right)+2{\mathrm{e}}^{-}⟶2{\mathrm{Br}}^{-}\left(\mathrm{aqueous}\right); {\mathrm{E}}^{\circ }=+1.08 \mathrm{V}$

Based one the data given above, reducing power of ${\mathrm{Fe}}^{2+}, \mathrm{Al}$ and ${\mathrm{Br}}^{-}$ will increase in the order:

The electrode potential becomes equal to standard electrode potential, when reactants and products concentration ratio is 

The $\mathrm{emf}$ of the cell, $\mathrm{Ni}\left|{\mathrm{Ni}}^{2+}\left(1.0 \mathrm{M}\right)\Vert {\mathrm{Ag}}^{+}\left(1.0 \mathrm{M}\right)\right|\mathrm{Ag}$  [$\mathrm{E}°$  for ${\mathrm{Ni}}^{2+}/\mathrm{Ni}=-0.25$ volt, $\mathrm{E}°$ for ${\mathrm{Ag}}^{+}/\mathrm{Ag}=0.80$ volt] is given by