1. Chemical Bonding In order to understand chemical bonding, we need to revisit the concepts we learned in Unit 2 on Valence Electrons. Valence Electrons are the electrons found in the outer-most shell of an element’s atomic model. There are seven electron shells available to place electrons. (refer to the diagram on the white board) The electrons in the outer-most shell are referred to as Valence Electrons.

2. Valence Electrons are the electrons responsible for bonding with other elements to create compounds. In order to understand chemical bonding with Valence Electrons, we refer to the Lewis Dot Model (often referred to as the electron-dot structure). The Lewis Dot Model is a model that only plots the Valence Electrons around the element symbol. The electrons are plotted in a north, south, west, east direction. (refer to diagram on side board)

3. Create atomic models and Lewis Dot Models for the following elements: C, Al, P, Li, and Mg The Lewis Dot Models informs us of how many Valence Electrons an element has and how many of these electrons have pairs. Knowing if the electrons are paired informs us of the element’s ability to bond with other elements and the element’s stability. Paired electrons = stability; nonbonding Unpaired electrons = unstable; bonding

4. Unpaired electrons can go through one of three forms of chemical bonding: ionic bonding, covalent bonding, and metallic bonding. Ionic bonding occurs when electrons are taken from one atom and given to another atom. This means that valence electrons are transferred. Electrons are lost and gained. Covalent bonding occurs when electrons are shared between atoms. This occurs between two or more nonmetals. Metallic bonding occurs when electrons between two or more metals are shared.

5. Covalent Bonding Covalent bonds form between nonmetals when the valence electrons are unpaired and unstable. In this kind of bonding, electrons are gained because they are shared. Hydrogen is our element that commonly forms covalent bonds because it is strongly attracted to other electrons. It is important to create the atomic model before the Lewis Dot Model so that you know the maximum number of electrons that can be shared. For example, Hydrogen can share one electron because it only contains one electron shell and that shell can have a maximum of two electrons.