THE PERIODIC TABLE

it's elementary, my dear Watson

A little history:

A really long time ago (like 1872) a Russian dude named Mendeleev decided to organize the elements into what we call the periodic table. Because not all elements had been discovered, Mendeleev left spaces for elements he assumed would be unearthed later. Mendeleev organized his periodic table by atomic mass. Then, in 1913, a British lad named Mosely decided to improve Mendeleev's work. He organized them by number into the periodic table we currently use. This was better because isotopes (which are versions of an element with a different number of n, and therefor a different mass) of elements were later discovered.

Types of Elements

There are 3 types of elements: metals, non-metals and metalloids. The metals are: Alkali Metals, Alkaline Earth Metals, and Transition Metals (Lanthanides and Actinides). The non-metals are Halogens and Noble Gases. The metalloids (which are sometimes metal and sometimes not) are found within the BCNO family.
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