<p class="sensei-content-description"><mark style="background-color:rgba(0, 0, 0, 0)" class="has-inline-color has-vivid-red-color">SUMMARY</mark></p> Atom is the smallest, electrically neutral particle of an element that can take part in a chemical reaction. IUPAC (International Union of Pure and Applied Chemistry) is an international scientific organisation which approves names of elements, symbols and units. Many of the symbols are the first one or two letters of the element’s name in English. The first letter of a symbol is always written as a capital letter (uppercase) and the second letter as a small letter (lowercase). For example, hydrogen, H; aluminium, Al and not AL; cobalt, Co and not CO. Other symbols have been taken from the names of elements in Latin, German or Greek. For example, the symbol of iron is Fe from its Latin name ferrum, sodium is Na from natrium, potassium is K from kalium. Therefore, each element has a name and a unique chemical symbol. <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>