Mendeleev's Periodic Table

Imagine searching for a specific book in a messy library where books are scattered everywhere without labels. Scientists faced a similar problem when trying to study and organize elements with a variety of physical and chemical properties.

In 1869, a Russian scientist named Dmitri Mendeleev solved this by creating a system to organize elements, similar to arranging books on shelves.

Mendeleev began by writing the names of elements on cards, including their properties like atomic mass and reactivity.

After putting eight elements in each row before moving to the next, a clear pattern emerged.

The vertical columns are known as groups, while the horizontal rows are called periods. Elements within a group share similar traits, almost like members of a family.

What made Mendeleev's work extraordinary was his ability to predict missing elements. He left blank spaces in his table where undiscovered elements would fit. Later, scientists found those elements and their properties matched his predictions perfectly.