Chapter 4 CARBON AND MOLECULAR DIVERSITY The Importance

Chapter 4 CARBON AND MOLECULAR DIVERSITY

The Importance of Carbon Organic chemistry is the study of carbon compounds Organic Chemistry – study of carbon compounds Organic Molecules – molecules that contain carbon Vitalism – belief on a life force outside the jurisdiction of chemical/physical laws Early researchers believed all organic molecules came from living organisms Mechanism – belief that all natural phenomena are governed by chemical/physical laws Researchers were able to synthesize organic compounds from Earth’s early atmospheric conditions

Carbon atoms are the most versatile building blocks of molecules With an atomic number of 6, there are 4 valence electrons to form 4 covalent bonds Carbon atom is usually the central point of all organic molecules

The Importance of Carbon (Continued) Carbon Skeleton Diversity Covalent bonds link carbon atoms together in long chains that form skeleton frameworks for organic molecules Vary in shape (branched, straight, ring), length, number and location of double bonds, and availability of other atoms to bond to sites on the skeleton

Hydrocarbons – molecules only containing H and C Major components of fossil fuels Isomers – compounds with the same molecular formula but with different structural arrangements and properties Structural Isomers – isomers that differ in covalent arrangement of their atoms Geometric Isomers – isomers which share covalent relationships but differ in spatial arrangement Enantiomers – isomers that are mirror images of each other

Functional Groups Functional groups contribute to the molecular diversity of life Functional groups are small characteristic groups of atoms who are frequently bonded to the carbon skeleton of organic molecules Regions of molecules that are chemically reactive Have specific physical/chemical properties

Hydroxyl Group – functional group that consists of a hydrogen atom bonded to an oxygen atom, which is then bonded to a carbon atom (-OH) Polar group Water soluble Forms hydrogen bonds with other polar molecules

Carbonyl Group- functional group that consists of a carbon atom double bonded to an oxygen atom (-CO) polar group; can be involved in H-bonding; makes molecule attached to it water soluble found in sugars Aldehydes-if the carbonyl group is at the end of a carbon skeleton.

Ketone – the carbonyl group will be in the middle of the molecule

Amino Group – functional group that consists of a nitrogen bonded to two hydrogen’s and to the carbon skeleton (-NH 2) Found in amino acids

Carboxyl Group – carbon atom double bonded to an oxygen and single bonded to an oxygen Found in amino acids

Sulfhydryl Group – a functional group that consists of sulfur bonded to a hydrogen (-SH)

Phosphate group – dissociated from a phosphoric acid Loses hydrogen ions; acidic properties Found in ATP (energy carrier molecule)