Medium INTEGER +4 / -1 PYQ · JEE Mains 2024

The total number of species from the following in which one unpaired electron is present, is _______.

$$\mathrm{N}_2, \mathrm{O}_2, \mathrm{C}_2^{-}, \mathrm{O}_2^{-}, \mathrm{O}_2^{2-}, \mathrm{H}_2^{+}, \mathrm{CN}^{-}, \mathrm{He}_2^{+}$$

Answer (integer) 4

Solution

<p><style type="text/css"> .tg {border-collapse:collapse;border-spacing:0;} .tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; overflow:hidden;padding:10px 5px;word-break:normal;} .tg th{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; font-weight:normal;overflow:hidden;padding:10px 5px;word-break:normal;} .tg .tg-baqh{text-align:center;vertical-align:top} .tg .tg-amwm{font-weight:bold;text-align:center;vertical-align:top} </style> <table class="tg" style="undefined;table-layout: fixed; width: 351px"> <colgroup> <col style="width: 175px"> <col style="width: 176px"> </colgroup> <thead> <tr> <th class="tg-amwm">Species</th> <th class="tg-amwm">Unpaired e</th> </tr> </thead> <tbody> <tr> <td class="tg-baqh">$<br>\mathrm{N}_2<br>$</td> <td class="tg-baqh">0</td> </tr> <tr> <td class="tg-baqh">$<br>\mathrm{O}_2<br>$</td> <td class="tg-baqh">2</td> </tr> <tr> <td class="tg-baqh">$<br>\mathrm{C}_2^{-}<br>$</td> <td class="tg-baqh">1</td> </tr> <tr> <td class="tg-baqh">$<br>\mathrm{O}_2^{-}<br>$</td> <td class="tg-baqh">1</td> </tr> <tr> <td class="tg-baqh">$<br>\mathrm{O}_2^{2-}<br>$</td> <td class="tg-baqh">0</td> </tr> <tr> <td class="tg-baqh">$<br>\mathrm{H}_2^{+}<br>$</td> <td class="tg-baqh">1</td> </tr> <tr> <td class="tg-baqh">$<br>\mathrm{CN}^{-}<br>$</td> <td class="tg-baqh">0</td> </tr> <tr> <td class="tg-baqh">$<br>\mathrm{He}_2^{+}<br>$</td> <td class="tg-baqh">1</td> </tr> </tbody> </table></p>

About this question

Subject: Chemistry · Chapter: Chemical Bonding and Molecular Structure · Topic: Ionic and Covalent Bonding

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