Periodic trends

Nota:

• image http://goo.gl/Ee8RjX

1. the distance between the nuclei of two atoms.
   1. covalent radius
      1. commonly used
   2. metallic radius
2. atomic radius increases from right to left and from top to bottom of the periodic table.

   Nota:

   • image http://goo.gl/aMDNmG
3. 2 main factors : effective nuclear charge (Z) and quantum number (n) of the outermost orbital
   1. higher Z, smaller size
   2. higher n, bigger size

1. Energy required to remove electron and create ion.
2. FIRST IONIZATION ENERGY IS THE ENERGY REQUIRED TO REMOVE AN OUTERMOST ELECTRON FROM A GROUND STATE ATOM IN GASEOUS STATE.
3. First ionization energy increases from bottom to top and left to right of the periodic table. (opposite trend to that of atomic size)

   Nota:

   • image http://goo.gl/vVp5US

1. energy change for the process of adding an electron to a neutral atom in the gaseous state to form a negative ion.
2. EA is usually a negative number, large negative number means it is easy to add electron into an atom.

   Nota:

   • image http://goo.gl/vAlZLA

1. The easier it is to remove electrons from an atom, the more metallic the element. (large atomic size, low Ei)
2. metallic character increases from right to left and from top to bottom of the periodic table.