Periodic - Table __top__

The number of protons in the nucleus. This defines what the element is.

Mendeleev’s true stroke of brilliance was leaving . He predicted that elements yet to be discovered would fill those gaps and even described their properties in detail. When elements like gallium and germanium were found later, they fit perfectly, proving his table was a law of nature, not just a list. Decoding the Tiles periodic table

Sitting on a "staircase" between metals and nonmetals, these elements (like Silicon) have properties of both. The number of protons in the nucleus

To understand the table, it helps to look at its major regions: He predicted that elements yet to be discovered

The large block in the middle (Groups 3-12) includes familiar names like Iron, Copper, and Gold. Why It Matters Today

Elements in the same group share similar "personalities." For example, Group 18 contains the Noble Gases—elements that are famously stable and rarely react with anything else. A Brief History: Mendeleev’s Masterpiece