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Chapter 1: Structure and Physical Properties of Organic Compounds UNIT 1 Chapter 1: Structure and Physical Properties of Organic Compounds Chapter 1: Structure and Physical Properties of Organic Compounds For thousands of years, scientists and Aboriginal peoples have been isolating organic compounds from natural materials, such as birch bark. The properties of these compounds make them useful in a wide variety of applications. TO PREVIOUS SLIDE

1.1 Introducing Organic Compounds UNIT 1 Chapter 1: Structure and Physical Properties of Organic Compounds Section 1.1 1.1 Introducing Organic Compounds Until the late 1800s, “organic” meant matter from living systems. “Inorganic” meant matter from non-living systems. Synthesis of urea (organic) from inorganic compounds forced scientists to reconsider their definitions. Modern Definitions Modern definitions of “organic” and “inorganic” are based on the presence of carbon and how the carbon atoms are bonded together. TO PREVIOUS SLIDE

The Special Nature of the Carbon Atom UNIT 1 Chapter 1: Structure and Physical Properties of Organic Compounds Section 1.1 The Special Nature of the Carbon Atom Important atomic properties of carbon: C has half of a filled outer shell & intermediate EN It is much more likely to share electrons than gain or lose electrons. Therefore, covalent bonding occurs with different elements – different structures & properties. It has four valence electrons. Therefore, it can be bonded to as many as four different atoms. Carbon has an atomic number of 6. On the periodic table, it is a main group element, in Period 2, Group 14. Carbon can bond to four different atoms, producing a molecule with a tetrahedron shape. TO PREVIOUS SLIDE

UNIT 1 Chapter 1: Structure and Physical Properties of Organic Compounds Section 1.1 Isomers Most organic molecules consist of more than one carbon atom bonded together in a chain or ring structure. Molecules with the same molecular formula but atoms in different arrangements are known as isomers. Constitutional or structural isomers: molecules with the same molecular formula, but the atoms are bonded in a different sequence. These molecules are constitutional isomers. TO PREVIOUS SLIDE

UNIT 1 Chapter 1: Structure and Physical Properties of Organic Compounds Section 1.1 Isomers Stereoisomers: molecules with the same molecular formula and sequence of atoms, but they differ in the three-dimensional orientation of their atoms diastereomer: stereoisomers based on the presence of a double bond enantiomer: stereoisomers that are mirror-images of each other. These molecules are diastereomers. TO PREVIOUS SLIDE

Answer on the next slide UNIT 1 Chapter 1: Structure and Physical Properties of Organic Compounds Section 1.1 Learning Check Are the following molecules isomers? If so, what type of isomers are they? Tips: First, determine if the two structures have the same molecular formula. Second, carefully look at how the atoms are bonded together. If they have the same molecular formula but the atoms are bonded together differently then they are constitutional isomers. Third, if the atoms are bonded together in the same arrangement and there is a multiple bond, determine if the groups attached to the carbon atoms involved in the double bond are different so that cis and trans forms are possible. Answer on the next slide TO PREVIOUS SLIDE

Learning Check UNIT 1 Yes they are isomers. Chapter 1: Structure and Physical Properties of Organic Compounds Section 1.1 Learning Check Yes they are isomers. They are stereoisomers, not constitutional isomers. TO PREVIOUS SLIDE

Section 1.1 Review UNIT 1 Section 1.1 Chapter 1: Structure and Physical Properties of Organic Compounds Section 1.1 Section 1.1 Review TO PREVIOUS SLIDE