The international year of the Periodic Table - 150th birthday

2019 has been designated the International Year of the Periodic Table because it marks 150 years since an early form of the periodic table was developed by a Russian Scientist called Dimitri Mendeleev. 

During his research, Mendeleev noticed that certain chemical elements shared similar properties. He arranged the elements by their atomic weight and thus discovered the Periodic Law, stating that there are clear patterns in the properties of the elements. His discovery was met slowly at first but eventually the periodic table was widely recognised and acclaimed on an international level. The periodic table has even been used to predict the presence of elements that had not been discovered yet. For example, Mendeleev, predicted the element gallium and its properties years before it was discovered! The Periodic Table is one of the most significant achievements in science, capturing the essence of not only chemistry, but also physics and biology.

The elements in the Periodic Table make up everything in the Universe and are arranged in such a way that we can easily understand their properties just by their location in the table. The periodic table is arranged into groups and periods. Groups are the columns going from top to bottom, and they describe how many electrons are in the outer shell of the element. For example, carbon is in group 4 and has 4 electrons in its outer shell. Periods are the rows going from left to right, and they tell us how many shells, or orbitals, an atom of that element has. For example, hydrogen is in period 1 and has 1 electron shell whereas potassium is in period 4 and has 4 electron shells.

Above, Developing Experts very own Dr. Sam Rowe discusses the Periodic Table and its elements with you. This is one of the many videos on the Periodic Table from our interactive science teaching platform, to view the rest of our teaching and learning content on the period table, sign up for a free trial account here.  

To find out even more about the periodic table, take a look at our range of Periodic Table lessons during your free 14 day trial to Developing Experts. During your free trial you’ll have full unlocked access to 700+ lessons for ages 4 - 14. Start trial here.