Introduction:

Dmitri Mendeleev, a Russian chemist, is credited with the development of the periodic table in the late 19th century. He used a specific property of elements to classify them in his periodic table, which revolutionized the understanding of chemical elements and their relationships.

Atomic Mass:

One of the most important properties that Mendeleev used to classify elements in his periodic table was their atomic mass. He arranged the elements in ascending order of atomic mass, creating a pattern that repeated at regular intervals. Mendeleev observed that elements with similar properties tended to have similar atomic masses. This led him to organize the elements in groups and periods, forming the basis for the modern periodic table.

Periods and Groups:

Mendeleev classified elements into horizontal rows called periods and vertical columns called groups. Each period represents the electron shells or energy levels of the elements, while each group contains elements with similar chemical properties. By arranging the elements in this manner, Mendeleev was able to identify patterns and trends in their properties.

Periodic Law:

Mendeleev's classification of elements based on atomic mass led to the formulation of the Periodic Law. This law states that the properties of elements are periodic functions of their atomic masses. In other words, the properties of elements repeat in a predictable manner across the periodic table, with similarities and trends occurring at regular intervals.

Properties and Trends:

Mendeleev's periodic table allowed for the prediction of properties of undiscovered elements. Gaps or missing elements in the table suggested the existence of yet-to-be-discovered elements with specific properties. Mendeleev accurately predicted the properties of some of these elements, which were later discovered and found to fit perfectly into his periodic table.

Summary:

In summary, Mendeleev used the property of atomic mass to classify elements in his periodic table. By arranging elements in ascending order of atomic mass, he identified patterns, trends, and similarities in their properties. This led to the development of the Periodic Law, which states that the properties of elements are periodic functions of their atomic masses. Mendeleev's periodic table laid the foundation for the modern understanding of elements and their relationships, allowing for the prediction of properties of undiscovered elements and advancing the field of chemistry.

mendeleev used 2 properties.They are chemical properties of the elements and atomic weights