1. Chapter 5 Lesson 3 Covalent Bonds Physical Science Unit 1

2. Start Up Answer the following question: How are molecules formed? Objectives: Explain covalent bonds Write electron-dot diagrams for simple molecules

3. Covalent Bonds A bond where valence electrons are shared between atoms Enables atoms to form molecules

4. Diatomic Molecule A molecule made up of two atoms of the same element Electrons are shared equally Only elements can have diatomic molecules: 1. Nitrogen 2. Oxygen 3. Hydrogen 4. Chlorine 5. Bromine 6. Iodine 7. Flouride

5. Hard to See! Covalent bonds are hard to visualize, so scientists came up with a diagramming method to show these bonds Called electron-dot diagram A model in which the chemical symbol represents the nucleus and all the filled inner energy levels of the atom and one dot represents each valence electron

6. Let’s Do it! Let’s do some electron dot diagrams together

7. Homework Complete electron-dot ws in packet Answer review questions