CHEMISTRY December 3, 2014 VALENCE ELECTRONS
SCIENCE STARTER Log onto the computer and do the Science Starter 12/3/2014 You are seated and silent You have 3 minutes
SS REVIEW Valence electrons are located where? What element is located at Period 3 Group 2? Which group has 3 valence electrons?
GROUPS NAME REVIEW Group 1 hydrogen (only H) Group 1 alkali metals (all but H) Group 2 alkaline earth metal Group 3-12 (collectively) transition metals Group 13 boron Group 14 carbon Group 15 nitrogen Group 16 chalcogens Group 17 halogens Group 18 Noble gases
VALENCE ELECTRONS The period number is the same as the number of occupied energy levels of an atom in its ground state. The outer most energy level (last number in the electron configuration) is the valence level and the electrons in this energy level are the valence electrons. In a chemical reaction, the valence electrons can be lost, gained or shared. Therefore, they determine the chemical properties of the elements.
VALENCE ELECTRON EXAMPLE Ca O Mg Ba Ne
LEWIS DOT STRUCTURE DEFINITION A WAY OF REPRESENTING ATOMS OR MOLECULES BY SHOWING ELECTRONS AS DOTS SURROUNDING THE ELEMENT SYMBOL
LEWIS DOT STRUCTURE FIND THE ELEMENT FIND THE ELECTRON CONFIGURATION DRAW THE LEWIS DOT STRUCTURE
LEWIS DOT STRUCTURE EXAMPLE Li
LEWIS DOT STRUCTURE He
LEWIS DOT STRUCTURE Li
LEWIS DOT STRUCTURE B
LEWIS DOT STRUCTURE O
LEWIS DOT STRUCTURE Ar
AIM Using R.A.C.E, respond to the following AIM prompt: What is the relationship between elements within the Alkali Metal group?