Properties, comparisons, quizzes & tools for learning chemistry
Noble gases · Period 2 · Group 18
A red-orange glow buzzing through the night. Bar signs, cinema marquees, hotel entrances — that warm, unmistakable light is neon. No other gas produces such a vivid glow. Just run an electric current through a glass tube filled with neon and it ignites. This effect was discovered over a century ago, and neon has been the symbol of nightlife ever since. But neon is more than signs. It is the fifth most abundant element in the universe, yet vanishingly rare on Earth. It is completely inert — it refuses to react with anything. Engineers use it in lasers, cryogenic systems, and plasma displays.
An electric car contains about 80 kg of copper — four times more than a gasoline car. Copper goes into the motor, battery, and all the wiring.
The periodic table consists of 18 groups (vertical columns) and 7 periods (horizontal rows). Elements in the same group share the same number of valence electrons, which determines their chemical behavior. Two additional rows — the lanthanides and actinides — are displayed separately.
The modern table contains 118 confirmed elements — from Hydrogen (H, #1) to Oganesson (Og, #118). Of these, 94 occur naturally, while the remaining 24 have been artificially synthesized in laboratories and particle accelerators.
Elements are divided into 11 categories based on their physical and chemical properties: alkali metals, alkaline earth metals, transition metals, post-transition metals, metalloids, nonmetals, halogens, noble gases, lanthanides, actinides, and unknown.
Explore elements with interactive tools: molar mass calculator, equation balancer, element comparison, property trend visualization, electron configurations, discovery timeline, and a chemistry quiz.
The periodic table of chemical elements is a fundamental tool of chemistry, created by Dmitri Mendeleev in 1869. Mendeleev arranged the 63 elements known at the time by increasing atomic weight and noticed that their chemical properties repeated periodically — hence the name "periodic table."
The modern table contains 118 confirmed elements organized by increasing atomic number (the number of protons in the nucleus). Elements are arranged in 7 horizontal rows (periods) and 18 vertical columns (groups). Elements in the same group share similar chemical properties because they have the same number of valence electrons.
How to read the table? Each cell contains the element's symbol, atomic number, and atomic mass. Colors indicate categories: alkali metals, transition metals, nonmetals, noble gases, and more. Elements on the left are metals, on the right are nonmetals, and in between are metalloids.
PeriodicTableHub helps you explore the table interactively. Click any element to see its properties, applications, and fun facts. Use the molar mass calculator to compute molecular weights, the equation balancer for chemical reactions, or take a quiz to test your knowledge. Compare up to 4 elements simultaneously or explore property trends across the entire table. View all tools →
This resource is designed for students, educators, and anyone curious about chemistry — from high school to university level.