Periodic Table

Periodic TableofElements

In 1860, Demetre Mendeleev looked for a pettern in the Periodic Table. He noticed the atoms get bigger, se he arranged it by their atomic mass. Some elements were missing, so he put a "?".Later, in 1914, Henry Moseley thought that the table should be arranged by atomic number, and everything fit perfectly. It is still arranged bty atomic number today.

Periodic Law

This states that properties of an element depend on the atomic number

It got it's name because it has a regular, repeating, pattern- so its periodic

blue : metalsyellow : non-metalsgreen : metalloids

olivia w.period 2

._._._._._._._._._._._._._

Metals

-found on the left side of the periodic table-almost empty outer clouds-are malleable (can be flattened)-are good conductors of heat and electricity-are ductile (stretche into a wire)-shiny

-surround the zig zag line-half full outer clouds (4)-shiny or dull-semi-conductors

Metalloids

Table Organization

-arranged in horizontal rows called periods-arramges in vertical columns called, or families-if they are in the same period/group they have similar properties

Chemical Symbols

Non-Metals

-always capitalize the first letter the first letter-abbreviation might be in other language

-found on the right side of the tablehave almost full clouds (7)-not shinyare brittle-poor conductors

Group 2 is made up of Alkaline Earth Metals-2 outer electrons-very reactive

Group 1 is made up of Alkali Metals-1 outer electron-very reactive

Valence Electrons: electrons in the outermost cloud of an atom

Groups 17-18 are Non-Metals

There are two rows on the bottom called Lnthanides & Actinides

Groups 3-12 are Transition Metals-1 or 2 valence electrons-less reactive than Groups 1 & 2-shiny and good conductors

Group 17 are Halogens-7 outer electrons-very reactive-fom salts

Group 18 are Noble Gases-8 valence electrons-unreactive

Groups 13-16 are Metalloids

Group 13 is the Boron Group-3 outer electrons-reactivity

Group 14 is the Boron Group-4 valence electron-reactivity varies

Group 15 is the Nitrogen Group-5 outer electrons -reactivity varies

Group 16 is the Oxygen Group-6 outer electrons-reactive

subtract 10 to find valence electrons Groups 12-18

Who Arranged It