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 title: 1
 description: 
 published: true
-date: 2026-02-11T16:02:17.712Z
+date: 2026-02-11T16:06:25.392Z
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 editor: ckeditor
 dateCreated: 2026-02-11T14:58:54.870Z
@@ -606,3 +606,13 @@ dateCreated: 2026-02-11T14:58:54.870Z
 </figure>
 <p>&nbsp;</p>
 <p>&nbsp;</p>
+<h3><span style="font-family:Arial, Helvetica, sans-serif;">Isotopes</span></h3>
+<p><span style="font-family:Arial, Helvetica, sans-serif;">If they have the same number of protons but different amount of neutrons</span></p>
+<p><span style="font-family:Arial, Helvetica, sans-serif;">For example, <sup>12</sup><sub>6</sub>C (Carbon-12) and <sup>14</sup><sub>6</sub>C (Carbon-14)</span></p>
+<p><span style="font-family:Arial, Helvetica, sans-serif;">The chemical properties will be the same as they have the same number of electron.</span></p>
+<p><span style="font-family:Arial, Helvetica, sans-serif;">The physical property will be slightly different.&nbsp;</span></p>
+<p>&nbsp;</p>
+<p><span style="font-family:Arial, Helvetica, sans-serif;">Iodine-131 is used in the detection and therapy of thyroid tumours.</span></p>
+<p><span style="font-family:Arial, Helvetica, sans-serif;">Iron-59 is used to monitor red blood cell production in bone marrow.</span></p>
+<p><span style="font-family:Arial, Helvetica, sans-serif;">Fluorine-18 is used for Positron Emission Tomography (PET) imaging tumors in oncology.</span></p>
+<p><span style="font-family:Arial, Helvetica, sans-serif;">Technetium-99m is used as a radioactive tracer and can be detected in the body by medical equipment (gamma cameras).</span></p>