The maximum work that can be obtained from the following cells is

$$ X\left|X^{2+}(a q) \| Y^{+}(a q)\right| Y $$

Given, $E_{X^{2+} / X}^{\circ}=-1.7 \mathrm{~V}, E_{Y^{2+} / Y}^{\circ}=0.8 \mathrm{~V}$

The specific rate constant of decomposition of a compound is given by $\ln k=5.0-\frac{12000}{T}$. The activation energy of decomposition for this compound at 300 K is

Which of the following statements is correct for chemisorption?

$$ \text { Match the following. } $$

$$ \begin{array}{llll} \hline & \text { Ores } & & \text { Composition } \\ \hline \text { A. } & \text { Calamine } & \text { (i) } & \mathrm{CuFeS}_2 \\ \hline \text { B. } & \text { Chalcopyrite } & \text { (ii) } & \mathrm{ZnCO}_3 \\ \hline \text { C. } & \text { Bauxite } & \text { (iii) } & \mathrm{Fe}_2 \mathrm{O}_3 \\ \hline \text { D. } & \text { Haematite } & \text { (iv) } & \mathrm{Al}_2 \mathrm{O}_3 \cdot 2 \mathrm{H}_2 \mathrm{O} \\ \hline \end{array} $$

$$ \text { The correct match is } $$