Periodic trends 2

Cation v anion

Cation: positive, lost electron, smaller than neutral, usu. metal

Anion: negative, gain electron, larger than neutral, usu. nonmetal

Atomic radius

1. one half of the distance between nucleus of two atoms of the same element.

Atomic radius (periodicity)

1. Increases going left (less protons→ less attraction)

2. Increases going down (more rings/more subatomic part.→ more repulsion)

What is Ionization energy

energy needed to remove outermost electrons

Ionization energy (periodicity)

1. Increases right (more valence → more energy to remove)

2. Increases going up (less rings →closer to nucleus → harder to remove)

Successive Ionization energies

Removing second electron requires more energy than removing the first one.

What is electron affinity

the change in energy that happens when an atom gains electrons. 

What happens when atoms gain electrons?

They release energy (more stable→ less energy)

Electron affinity (periodicity)

Increases: to the right (closer to full shell)

Increases: going up (less shells→ more proton attraction)

Metallic and nonmetallic (periodicity)

Metallic:increases from top right to bottom left

Nonmetallic: increases bottom left to top right

Oxidation vs reduction

Oxidation: losing electrons (positive)

Reduction: gaining electrons (negative)

Electronegativity

tendency of an atom to attract electrons

Electronegtaivity (periodicity)

Increases: to right

Increases to the top

Melting/boiling point relations

Tighter rings/bonds = higher melting point (increases moving right) (increases moving down)

Exception: halogens & noble gases = increase with larger atom

Reactivity (periodicity)

Metals: INCREASES reactivity going DOWN (weaker bond, easier to lose electron)

Nonmetals: INCREASES going UP (stronger bond, easier to gain electrons)

Relationship between rings and attraction

Less rings → more attraction

Relationship between protons and attraction

More protons → more attraction