Covalent Bonding Chapter 8

Molecules A molecule is a neutral group of atoms held together by covalent bonds. In a covalent bond atoms share electrons.

Molecular Compounds A compound composed of molecules is a molecular compound. They have lower melting points than ionic compounds, are gases or liquids at room temperature, and are made of 2 non metals.

Diatomic Molecules A diatomic molecule is a molecule made of two atoms of the same element. You must memorize that the following 7 atoms are always found as diatomic molecules: H 2, N 2, O 2, F 2, Cl 2, I 2, Br 2

Octet Rule In covalent bonds, electrons are shared so that each atom in the molecule has 8 valence electrons.

Single Covalent Bond Two atoms held together by sharing one pair of electrons are joined by a single covalent bond. For example, H 2, which can be written as H:H or H-H

Double and triple Covalent Bonds A bond in which 2 electron pairs are shared is a double bond. Example O 2 A bond in which 3 electron pairs are shared is a triple bond. Example N 2

Polar and Non-polar covalent bonds If electrons are shared equally between atoms in a covalent molecule, we call this non-polar. It has no charge. If electrons are NOT shared equally, this is called polar. Water is polar.

Other Bonds and Forces Dipole Interactions happen when 2 polar molecules are attracted to each other. Dispersion forces are very weak forces caused by the motion of electrons in any molecule. Both of the above are types of van der Waals forces. Hydrogen bonds are when a slightly positive hydrogen is attracted to a slightly negative atom of another molecule.

Unit 3 Test 1. Complete the Review sheet (due next class) 2. Review your notes on Lewis Dots, Ionic and Metallic bonds, and Covalent bonds *no notebook collection for this test! 25 questions, multiple choice

Complete the Chart NameChemical FormulaElectron Dot Structure Fluorine Chlorine Bromine Iodine Hydrogen Nitrogen Oxygen

Complete the Chart NameChemical FormulaElectron Dot Structure FluorineF2F2 ChlorineCl 2 BromineBr 2 IodineI2I2 HydrogenH2H2 NitrogenN2N2 OxygenO2O2

Complete the Chart NameChemical FormulaElectron Dot Structure FluorineF2F2 ChlorineCl 2 BromineBr 2 IodineI2I2 HydrogenH2H2 H-H NitrogenN2N2 OxygenO2O2

Quiz and Notebook Check on Monday! Period 3: Warm-ups Notes (Nuclear Chem, Lewis, Ionic, Covalent) Nuclear Rxn Worksheet (stapled) P802 (1-6), P Unit 1 Review (stapled) P207 (30-47) Ionic and Metallic bonds worksheet (stapled)

Quiz and Notebook Check on Monday! Period 5: Warm-ups Notes (Nuclear Chem, Lewis, Ionic, Covalent) Nuclear Rxn Worksheet (stapled) P802 (1-6), P Unit 1 Review (stapled) Ionic and Metallic bonds worksheet (stapled)