Explore Mendeleev’s periodic table in an interactive format featuring all 118 chemical elements, detailed properties, category filters, color-coded groups, and physical state information.
The Mendeleev periodic table of elements organizes chemical elements by atomic number, revealing repeating patterns in their structure, electron configuration, and chemical behavior. Building on Dmitri Mendeleev’s original work, the modern layout places lanthanides and actinides below the main table to keep the element chart clear and easy to navigate.
This interactive periodic table allows you to explore the 118 known elements using different display modes, atomic data views, and category filters. You can compare element families, examine trends such as electronegativity, atomic radius, and density, and even see how the physical state of elements changes at different temperatures—all in one searchable reference.
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Periodic Table FAQ
What is the Mendeleev periodic table?
The Mendeleev periodic table is the foundation of the modern periodic table of elements. Dmitri Mendeleev organized the known chemical elements by recurring physical and chemical properties, creating a system that later evolved into the atomic-number-based periodic table used today.
Who was Dmitri Mendeleev and why is he important?
Dmitri Mendeleev was a well-known chemist who published one of the first successful periodic tables in 1869. His arrangement of elements revealed repeating patterns in chemical behavior and helped establish the structure of the modern periodic table.
How did Mendeleev predict undiscovered elements?
Mendeleev noticed gaps in his periodic table where no known element fit the expected pattern. He predicted the existence and properties of several missing elements, and many of those predictions were later confirmed by scientific discovery.
How many elements are in the modern periodic table?
The modern periodic table contains 118 confirmed chemical elements. It begins with hydrogen, atomic number 1, and currently ends with oganesson, atomic number 118.
Why is the periodic table arranged by atomic number instead of atomic mass?
The modern periodic table is organized by atomic number because the number of protons defines each element. This system provides a more accurate explanation of recurring chemical properties than older atomic-mass-based arrangements used in early versions of the Mendeleev table.
Why are lanthanides and actinides placed below the periodic table?
Lanthanides and actinides belong to the main periodic sequence, but they are usually displayed below the table to keep the layout compact and easier to read. This format preserves the structure of the periodic table while improving usability.