Why is standard hydrogen electrode called reference electrode? An electrochemical cell connects \( \text{E}^\circ_{\text{Zn}^{++}/\text{Zn}} \)…
Class 12 Chemistry · 2083 · Solved Question with Answer
Why is standard hydrogen electrode called reference electrode?
An electrochemical cell connects \( \text{E}^\circ_{\text{Zn}^{++}/\text{Zn}} \) electrode with standard hydrogen electrode and the emf of the cell is found to be \( +0.76 \text{ V} \)
i) Design cell notation indicating cathode and anode.
ii) Write down net cell reaction.
iii) What is the value of \( \text{E}^\circ_{\text{Zn}^{++}/\text{Zn}} \)?
OR
a) State Hess's law of constant heat summation and illustrate it with an example.
b) Heat of formation of \( \text{CO}_2 \) and \( \text{H}_2\text{O} \) are \( -94 \text{ kcal} and -68 \text{ kcal} \), respectively. Calculate heat of reaction when 2 mole of \( \text{CH}_4 \) is formed.