Given below are two statements :
Statement I : The limiting molar conductivity of KCl (strong electrolyte) is higher compared to that of CH3COOH (weak electrolyte).
Statement II : Molar conductivity decreases with decrease in concentration of electrolyte.
In the light of the above statements, choose the most appropriate answer from the options given below :
Solution
<table class="tg">
<thead>
<tr>
<th class="tg-c3ow">Ion</th>
<th class="tg-c3ow">${H^ + }$</th>
<th class="tg-c3ow">${K^ + }$</th>
<th class="tg-c3ow">$C{l^ - }$</th>
<th class="tg-baqh">$C{H_3}CO{O^ - }$</th>
</tr>
</thead>
<tbody>
<tr>
<td class="tg-c3ow">$\Lambda _{m\,Sc{m^2}/mole}^\infty$</td>
<td class="tg-c3ow">349.8</td>
<td class="tg-c3ow">73.5</td>
<td class="tg-c3ow">76.3</td>
<td class="tg-baqh">40.9</td>
</tr>
</tbody>
</table><br><br>So, <br><br>$$\Lambda _{m\,\,C{H_3}COOH}^\infty = \Lambda _{m\,\,({H^ + })}^\infty + \Lambda _{m\,\,C{H_3}CO{O^ - }}^\infty $$<br><br>= 349.8 + 40.9 = 390.7 Scm<sup>2</sup>/mole<br><br>$$\Lambda _{m\,\,KCl}^\infty = \Lambda _{m\,\,({K^ + })}^\infty + \Lambda _{m\,\,(C{l^ - })}^\infty $$<br><br>= 73.5 + 76.3 = 149.3 Scm<sup>2</sup>/mole<br><br>So, Statement I is wrong or false.<br><br>As the concentration decreases, the dilution increases which increases the degree of dissociation, thus increasing the no. of ions, which increases the molar conductance.<br><br>So Statement II is false.<br><br>Image
About this question
Subject: Chemistry · Chapter: Electrochemistry · Topic: Electrochemical Cells
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