In which of the following arrangements, the order is not strictly according to the property written against it?
For a $$\mathrm{Ag}-\mathrm{Zn}$$ button cell, net reaction is
$$\begin{gathered} \mathrm{Zn}(s)+\mathrm{Ag}_2 \mathrm{O}(s) \longrightarrow \mathrm{ZnO}(s)+2 \mathrm{Ag}(s) \\ \Delta G_f^{\circ}\left(\mathrm{Ag}_2 \mathrm{O}\right)=-11.21 \mathrm{~kJ} \mathrm{~mol}^{-1} \\ \Delta G_f^{\circ}(\mathrm{ZnO})=-318.3 \mathrm{~kJ} \mathrm{~mol}^{-1} \end{gathered}$$
Then, $$E^{\circ}$$ cell of the button cell is
Which of the following oxyacid does not contain $$\mathrm{P}-\mathrm{O}-\mathrm{P}$$ bond?
Niobium crystallises in body centred cubic structure. If density is $$8.55 \mathrm{~g} \mathrm{~cm}^{-3}$$, then the atomic radius of niobium is (atomic mass of niobium $$=93 u$$ )