An electrochemical cell (galvanic cell) is designed by coupling Zn-electrode with standard hydrogen electrode (SHE). Given, \( E^\circ_{Zn^{++}/Zn} =…
Class 12 Chemistry · 2081 · Solved Question with Answer
An electrochemical cell (galvanic cell) is designed by coupling Zn-electrode with standard hydrogen electrode (SHE). Given, \( E^\circ_{Zn^{++}/Zn} = -0.76\text{ V} \)
i) Draw the galvanic cell.
ii) Write down complete cell reaction.
iii) Calculate the emf of the cell.
OR
What is Hess's law of constant heat summation? Calculate the heat of formation of ethanol from the following data:
\( H_2(g) + \frac{1}{2}O_2(g) \rightarrow H_2O(l), \Delta H = -286.2\text{ KJ/mol} \)
\( C(s) + O_2(g) \rightarrow CO_2(g), \Delta H = -393.2\text{ KJ/mol} \)
\( C_2H_5OH(l) + 3O_2(g) \rightarrow 2CO_2(g) + 3H_2O(l), \Delta H = -1368\text{ KJ/mol} \)