Which of the following hot aqueous solutions is used to dip carbon rods of \(\text{H}_2-\text{O}_2\) fuel cell ?
Show Hint
- \(\text{KCl}\)
- \(\text{KOH}\)
- \(\text{H}_2\text{SO}_4\)
- \(\text{NH}_4\text{Cl}\)
The Correct Option is B
Solution and Explanation
Each electrode is a porous carbon rod holding finely divided catalyst (Pt or Pd), with the gases bubbled in.
Step 2: Electrolyte
The reactions consume and produce OH$^-$, so the electrolyte is a hot concentrated KOH solution. That is option (B).
Final Answer:
The fuel cell uses hot aqueous KOH, option (B). \[ \boxed{\text{KOH}} \]
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