THE PERIODIC TABLE Topic 5

Scientist to know  Dmitri Mendeleev  A Russian chemist  He built the periodic table. How? He made element cards with data about each element He pinned them all to the wall in order of increasing atomic mass He left gaps in the periodic table for elements to still be discovered He predicted the existence and physical properties of the missing elements because the elements follow a pattern. Gallium and germanium were discovered shortly after. This is an example of experimental evidence confirming a scientific prediction.

 st=PLJicmE8fK0Ehrg3meytY7DT8LJiwuU3Th&index =96 st=PLJicmE8fK0Ehrg3meytY7DT8LJiwuU3Th&index =96  The genius of Mendeleev's periodic table - Lou Serico

Groups and Periods  Vertical columns are called groups  Horizontal rows are called periods   Element song animated  d d  First 10 song

Each element The charge an atom becomes after it has given or taken e - s Given by the person who discovered it. Either the first letter of the name, first two letters of the name, two letters from the name, or letters from the Latin name. Mass of the protons + mass of the neutrons Each proton and neutron has an approximate mass of 1 amu or g/mol Round each atomic mass to the nearest whole number # neutrons = atomic mass – atomic number Amu = atomic mass unitg/mol = the mass of 1 mol of atoms1 mol = 6.02 x atoms Number of protons

Assignment 1. Element Symbols 2. Using the Periodic Table *back page 3. Chemistry Dictionary – up to Topic 5