<p class="sensei-content-description"><strong><mark style="background-color:rgba(0, 0, 0, 0)" class="has-inline-color has-vivid-cyan-blue-color">Radioactive Element</mark></strong></p> It was previously believed that the atom is the smallest indivisible particle of an element. Further work by scientists on the structure of atoms disprove this belief. It is now known that some atoms split naturally by themselves to form new atoms, and in the process give out heat and light energies called radiation or radiant energy. <div class="sign-up-notice-after-excerpt-two" style="background-color:powderblue;"> You are viewing an excerpt of this lesson. Subscribing to the subject will give you access to the following: <ul> <li>The complete lesson note and evaluation questions for this topic</li> <li>The complete lessons for the subject and class (First Term, Second Term & Third Term)</li> <li>Media-rich, interactive and gamified content</li> <li>End-of-lesson objective questions with detailed explanations to force mastery of content</li> <li>Simulated termly preparatory exams</li> <li>Discussion boards on all lessons and subjects</li> <li>Guaranteed learning</li> <li>Win great prizes for topping the <a href="https://www.primacyebooks.com">Primacy Ebooks</a></li> </ul> </div> <div class="sensei-message info"></div>