Electron Affinity The energy change that occurs when a neutral atom acquires an electron. Most electron affinity values are negative. Energy is released from the atom. Atoms that really want another electron tend to be more negative.
Electron Affinity Trends Top to Bottom Left to Right Decreases (less negative) Increases (more negative) Noble Gases = 0
Ionization Energy The energy required to remove one electron from a neutral atom. The closer to the nucleus, the harder to pull the electron. The farther away, more interference from other electrons, therefore, the easier it is to pull the electron.
Electronegativity A measurement of the ability of an atom in a chemical compound to attract electrons.
Generally, Ionization energy + Electron Affinity = Electronegativity Ionization energy + Electron Affinity = Electronegativity Most electronegative element – Fluorine (F) Most electronegative element – Fluorine (F) It is assigned the number 4 It is assigned the number 4 All other values are based on this value. All other values are based on this value.
Top to Bottom Left to Right Increase Increases then Decreases
Boiling Point Temperature at which a system moves from the liquid state to the gaseous state. The external pressure pushing into the liquid is equal to the internal pressure pushing out of the liquid.
Melting Point The temperature at which a solid becomes a liquid. The external pressure pushing into the solid is equal to the internal pressure pushing out of the solid.