The reaction
$$\frac{1}{2} \mathrm{H}_{2}(\mathrm{~g})+\mathrm{AgCl}(\mathrm{s}) \rightleftharpoons \mathrm{H}^{+}(\mathrm{aq})+\mathrm{Cl}^{-}(\mathrm{aq})+\mathrm{Ag}(\mathrm{s})$$
occurs in which of the given galvanic cell.
Solution
<p>The provided reaction is:</p>
<p>$$\frac{1}{2} \mathrm{H}_{2}(\mathrm{~g})+\mathrm{AgCl}(\mathrm{s}) \rightleftharpoons \mathrm{H}^{+}(\mathrm{aq})+\mathrm{Cl}^{-}(\mathrm{aq})+\mathrm{Ag}(\mathrm{s})$$</p>
<p>This reaction involves the following half-reactions:</p>
<ol>
<li>Oxidation of hydrogen gas to H+ ions: $$\frac{1}{2} \mathrm{H}_{2}(\mathrm{~g}) \rightleftharpoons \mathrm{H}^{+}(\mathrm{aq}) + e^-$$</li><br/>
<li>Reduction of AgCl to Ag: $$\mathrm{AgCl}(\mathrm{s}) + e^- \rightleftharpoons \mathrm{Ag}(\mathrm{s}) + \mathrm{Cl}^{-}(\mathrm{aq})$$</li>
</ol>
<p>Looking at the options provided:</p>
<p>Option A: Doesn't involve H<sub>2</sub> gas, so it can't be correct.</p>
<p>Option B: This includes the necessary elements - H<sub>2</sub>, AgCl, and Ag. </p>
<p>Option C: Doesn't involve AgCl, so it can't be correct.</p>
<p>Option D: Also includes the necessary elements - H<sub>2</sub>, AgCl, and Ag.</p>
<p>However, looking closely, we can see that Option B represents the galvanic cell for this reaction. The reaction requires the oxidation of H<sub>2</sub> to H<sup>+</sup>, which occurs at the anode. The reaction also requires the reduction of AgCl to Ag and Cl-, which occurs at the cathode.</p>
<p>In Option B, the anode (on the left) is where H<sub>2</sub> is being oxidized to H<sup>+</sup>. The cathode (on the right) is where AgCl is reduced to Ag and Cl<sup>-</sup>. The salt bridge or ion exchange component is HCl, which allows for the flow of ions to balance charge in the cell.</p>
<p>Therefore, the reaction occurs in the galvanic cell represented by Option B.</p>
About this question
Subject: Chemistry · Chapter: Electrochemistry · Topic: Electrochemical Cells
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