Trends in the Periodic Table Atomic Mass Atomic Radius Ionization Energy Electronegativity Density Electron Affinity

Trends in the Periodic Table Atomic Mass - The represents two things; Mass of an atom in amu (Atomic Mass Units), the Molar Mass in grams/mole Slope of line is very consistent, therefore predictable As Atomic # Increases, Atomic Mass increases linearly

Trends in the Periodic Table Atomic Radius In each Row the Radius Decreases Moving to Increasing Rows the Radius Increases

Trends in the Periodic Table Atomic Radius

Trends in the Periodic Table Why does Radius decrease as electrons are added across a row? Larger nucleus More Protons More Electrostatic force

Trends in the Periodic Table Ionization Energy – Energy required to remove an electron from a neutral atom of an element. How strong an element holds on to its outer most electron. Measure in Joules. A + Energy  A + + e -

Trends in the Periodic Table Ionization Energy Trend in Periodic Table IE increases as you move from Left to Right across Periodic Table IE decreased as you move down the Periodic Table

Trends in the Periodic Table Electronegativity – desire for electrons Electronegativity increases as you move from Left to Right across Periodic Table EN decreased as you move down the Periodic Table

Trends in the Periodic Table Density Density is high in the middle of the row and low on the ends As you move down the Periodic Table the Density of things increases

Trends in the Periodic Table Electron Affinity – The energy change that occurs when an electron is acquired by a neutral atom. Most atoms give away energy when they acquire an electron. Energy given away is given the sign (-). A + e -  A - + Energy Some atoms must be forced to gain an electron by the addition of Energy. A + Energy + e -  A -

Trends in the Periodic Table Electron Affinity – This one is a bit difficult to sort out.

Trends in the Periodic Table Electron Affinity – Add some lines to see the pattern

Trends in the Periodic Table Electron Affinity- green lines indicate general trend Affinity decreases as you move from left to right.

Trends in the Periodic Table Summary