JEE Mains · Chemistry · STD 12 - 2. Electrochemistry
What pressure (bar) of \(\mathrm{H}_2\) would be required to make emf of hydrogen electrode zero in pure water at \(25^{\circ} \mathrm{C}\) ?
- A \(10^{-14}\)
- B \(10^{-7}\)
- C \(1\)
- D \(0.5\)
Answer & Solution
Correct Answer
(A) \(10^{-14}\)
Step-by-step Solution
Detailed explanation
\(2 \mathrm{e}^{-}+2 \mathrm{H}^{+}(\mathrm{aq}) \rightarrow \mathrm{H}_2(\mathrm{~g})\) \(\mathrm{E}=\mathrm{E}^0-\frac{0.059}{\mathrm{n}} \log \frac{\mathrm{P}_{\mathrm{H}_2}}{\left[\mathrm{H}^{+}\right]^2}\)…
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