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The periodic table organizes all known elements by atomic number, displaying them in rows and columns called periods and groups. Each element’s square includes its symbol, atomic number, and atomic mass. Groups of elements often share similar properties, like the reactive metals in Group 1, and the inert noble gases in Group 18. The table also separates metals, nonmetals, and metalloids, helping us see patterns in elemental behavior and relationships.

00:00 Intro
00:22 Symbols are universal
00:53 Atomic number & atomic mass
02:46 Metals, nonmetals, & metalloids
03:32 Periods and groups
05:01 Alkali metals
05:24 Alkaline Earth metals
05:40 Halogens
06:15 Noble gases


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