Periodic table

Periods

seven rows, left to right corresponding yo a energy level (1s, 2s, 3s, etc)

Groups

Columns of an element that share similar properties

Representative elements

Group A 1, 2, 13, 14, 15, 16, 17, 18

Transition metals

Group B 3-12

Alkali metals

Group 1A, most reactive unstable metals, want to react with other elements to form compounds, reactivity INCREASES down the group

Alkaline earth metals

Group 2A, second most reactive unstable metal, want to react with other elements to form compounds, reactivity INCREASES down the group

Transition metals

Group 3B - 12B, includes the rare earth elements found in compounds, less reactive than groups 1 and 2

Nonmetals

In the upper right corner above the staircase + hydrogen, opposite of metals (poor conductors of heat and electricity & gases or brittle solids)

metals

Everything legt of staircase, Generally shiny when smooth and clean; solid at room temp, has good cpnductors of heat and electrcity

Halogens

Group 17A, most reactive unstable nonmetals, reactivity DECREASES down the group

Noble Gases

group 18A, most stable elements, inert (unreactive, won’t form compounds)

Metalloids

Have physical and chemical properties of metals and non-metals, along the staircase

Coulomb’s law

how strong the attraction is between protons & electrons, includes the amount of charge (larger charge = stronger attraction) and the distance between charges (closer together protons are to electrons, the stronger the attraction)

Atomic radius

distance from nucleus to the outermost electron

Cations

Positive ions, if an atom loses an electron, it loses a negative charge, becoming positive, typically metals, SMALLER than parent atom

Anions

atom gains an electron, it. adds a negative charge becoming negative, typically nonmetals, larger than parent atom

Ionization energy

energy required to steal an electron from an atom

High ionization

atom has a strong hold of its electrons = harder to steal from

Low ionization

Atom has a weak hold of electrons = easier to steal

Electronegativity

predicts the type of bond that will form during a reaction, decreases down a group and increases left to right