Periodic Trends
Atomic Radius Total distance from an atoms nucleus to the outermost orbital of an electron (similar to the radius of a circle where the center is the nucleus) Measured by half of the distance between two bonding atoms nuclei This is because the atom doesn’t have a defined edge affected by both the number of protons and distance of which its valance electrons
Atomic Radius Trend Increases Increases
Ionic Radius radius of an atoms ion Trend compares ions to their neutral counterparts Can look at general trends among cations and anions respectively, NOT all together
Ions Variation in the number of electrons; results in an atom becoming charged Anion Cation gain of electrons overall charge is negative lose of electrons overall charge is positive 11 protons 12 neutrons 11electrons 10 electrons Sodium atom Sodium ion 1+ Na 1− F
Cations and Anions Of Representative Elements +1 +2 +3 -3 -2 -1
Cation vs Atom Increasing Cation Radius Increasing Cation Radius
Anion vs Atom Increasing Anion Radius Increasing Anion Radius
General Trend in Ionic Radius Cation is always smaller than atom from which it is formed. Anion is always larger than atom from which it is formed.
Ionization Energy Minimum energy required to remove an electron from a gaseous atom in its ground state Indication of how strongly an atom’s nucleus holds onto its valence electron (columbic attraction)
What do you notice between successive ionization energies What do you notice between successive ionization energies? What is the trend across and down?
General Trend in First Ionization Energies Increasing First Ionization Energy Increasing First Ionization Energy
Electronegativity Chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself An atoms electronegativity is affected by both its atomic number and the distance at which its valance electrons reside from the charged nucleus (columbic attraction)
Electronegativity Values The most electronegative element
General Trend in Electronegativity