Chemistry · Electrochemistry

JEE Main 2024 — 4 April, Shift 1 — Question 59

What pressure (bar) of H2\mathrm{H}_{2} would be required to make emf of hydrogen electrode zero in pure water at 25∘C25^{\circ} \mathrm{C} ?

  1. Option A:

    10−1410^{-14}

    Correct
  2. Option B:

    10−710^{-7}

  3. Option C:

    1

  4. Option D:

    0.5

Answer: A

Step-by-step solution

2e−+2H+(aq)→H2( g)2 \mathrm{e}^{-}+2 \mathrm{H}^{+}(\mathrm{aq}) \rightarrow \mathrm{H}_{2}(\mathrm{~g})

\begin{array}{*{35}{r}}{} & \text{E}={{\text{E}}^{\text{o}}}-\frac{0.059}{\text{n}}\text{log}\frac{{{\text{P}}_{{{\text{H}}_{2}}}}}{{{\left[ {{\text{H}}^{+}}\right]}^{2}}}\\{}&0=0\frac{0.059}{2}\text{log}\frac{{{\text{P}}_{{{\text{H}}_{2}}}}}{{{\left({{10}^{-7}} \right)}^{2}}} \\{} & \text{log}\frac{{{\text{P}}_{{{\text{H}}_{2}}}}}{{{\left( {{10}^{-7}} \right)}^{2}}}=0 \\{} & \frac{{{\text{P}}_{{{\text{H}}_{2}}}}}{{{10}^{-14}}}=1 \\{} & {{\text{P}}_{{{\text{H}}_{2}}}}={{10}^{-14}}\text{bar} \\\end{array}

Answer key and solution verified before publishing.

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Exam
JEE Main 2024
Subject
Chemistry
Chapter
Electrochemistry
Topic
Nernst Equation and Electrochemical Series
What pressure (bar) of H 2 would be required to make emf of hydrogen… | JEE Main 2024 PYQ with Solution · DhiX AI