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 title: 1
 description: 
 published: true
-date: 2026-02-11T15:42:38.277Z
+date: 2026-02-11T15:48:58.466Z
 tags: 
 editor: ckeditor
 dateCreated: 2026-02-11T14:58:54.870Z
@@ -390,3 +390,64 @@ dateCreated: 2026-02-11T14:58:54.870Z
 <p><span style="font-family:Arial, Helvetica, sans-serif;">Noble gases are stable in atomic form because the outermost shell are fully filled.</span></p>
 <p><span style="font-family:Arial, Helvetica, sans-serif;">Other element tend to lose, gain or share electron to achieve nearest fully filled electronic structure, that is duplet or octet structure.</span></p>
 <p>&nbsp;</p>
+<h3><span style="font-family:Arial, Helvetica, sans-serif;">Cation</span></h3>
+<p><span style="font-family:Arial, Helvetica, sans-serif;">Atom that loses e-, +ve ions</span></p>
+<p><span style="font-family:Arial, Helvetica, sans-serif;">Usually group 1 and 2. Like Li<sup>+</sup>, Na<sup>+</sup>, Mg<sup>2+</sup></span></p>
+<p><span style="font-family:Arial, Helvetica, sans-serif;">For transition metal, 4s electron will be lost first. Like Ti<sup>2+</sup>, Cu<sup>+</sup></span></p>
+<p>&nbsp;</p>
+<figure class="table">
+  <table>
+    <tbody>
+      <tr>
+        <td style="text-align:center;width:150px;">&nbsp;</td>
+        <td style="text-align:center;width:200px;"><span style="font-family:Arial, Helvetica, sans-serif;"><strong>Name</strong></span></td>
+        <td style="text-align:center;width:200px;"><span style="font-family:Arial, Helvetica, sans-serif;"><strong>Color (Water)</strong></span></td>
+      </tr>
+      <tr>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Li<sup>+</sup></span></td>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Lithium ion</span></td>
+        <td style="text-align:center;" rowspan="10"><span style="font-family:Arial, Helvetica, sans-serif;">Colorless</span></td>
+      </tr>
+      <tr>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Na<sup>+</sup></span></td>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Sodium ion</span></td>
+      </tr>
+      <tr>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">K<sup>+</sup></span></td>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Potassium ion</span></td>
+      </tr>
+      <tr>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Ag<sup>+</sup></span></td>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Silver ion</span></td>
+      </tr>
+      <tr>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Mg<sup>2+</sup></span></td>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Magnesium ion</span></td>
+      </tr>
+      <tr>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Ca<sup>2+</sup></span></td>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Calcium ion</span></td>
+      </tr>
+      <tr>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Zn<sup>2+</sup></span></td>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Zinc ion</span></td>
+      </tr>
+      <tr>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Pb<sup>2+</sup></span></td>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Lead (II) ion</span></td>
+      </tr>
+      <tr>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Al<sup>3+</sup></span></td>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Aluminium ion&nbsp;</span></td>
+      </tr>
+      <tr>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">NH<sub>4</sub><sup>+</sup></span><br><span style="font-family:Arial, Helvetica, sans-serif;">(Polyatomic)</span></td>
+        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Ammonium ion</span></td>
+      </tr>
+    </tbody>
+  </table>
+</figure>
+<p>&nbsp;</p>
+<h3><span style="font-family:Arial, Helvetica, sans-serif;">Anion</span></h3>
+<p><span style="font-family:Arial, Helvetica, sans-serif;">Atom that gains e-, -ve ions</span></p>
+<p>&nbsp;</p>