Chapter: Carbon Chemistry

2. Table of Contents Chapter: Carbon Chemistry Section 1: Simple Organic Compounds Section 2: Other Organic Compounds Section 3: Biological Compounds

3. Simple Organic Compounds 1 Organic Compounds • Carbon’s ability to bond easily and form compounds is the basis of life on Earth. • A carbon atom has four electrons in its outer energy level, so it can form four covalent bonds with as many as four other atoms. • One of carbon’s most frequent partners in forming covalent bonds is hydrogen.

4. Simple Organic Compounds 1 Organic Compounds • Substances can be classified into two groups those derived from living things and those derived from nonliving things. • Most of the substances associated with living things contain carbon and hydrogen. • Scientists use the termorganic compoundfor most compounds that contain carbon.

5. Simple Organic Compounds 1 Hydrocarbons • A compound that contains only carbon and hydrogen atoms is called ahydrocarbon. • The simplest hydrocarbon is methane. • Methane consists of a single carbon atom covalently bonded to four hydrogen atoms.

6. Simple Organic Compounds 1 Hydrocarbons • This figure shows a model of the methane molecule and its structural formula. • In a structural formula, the line between one atom and another atom represents a pair of electrons shared between the two atoms.

7. Simple Organic Compounds 1 Hydrocarbons • Here’s a way to visualize how larger hydrocarbons are built up.

8. Simple Organic Compounds 1 Saturated Hydrocarbons • When all the bonds in a hydrocarbon are single bonds, the molecule is called asaturated hydrocarbon. • No additional hydrogen atoms can be added to the molecule.

9. Simple Organic Compounds 1 Saturated Hydrocarbons • Propane, with three carbon atoms, is the third member of the series of saturated hydrocarbons. • Butane has four carbon atoms.

10. Simple Organic Compounds 1 Saturated Hydrocarbons • Saturated hydrocarbons are named with an –ane ending. Another name for these hydrocarbons is alkanes. • Page 411

11. Simple Organic Compounds 1 Saturated Hydrocarbons • Carbon can form long chains that contain hundreds or even thousands of carbon atoms. • These extremely long chains make up many of the plastics that you use.

12. Simple Organic Compounds 1 Unsaturated Hydrocarbons • Hydrocarbons with double or triple bonds are calledunsaturated hydrocarbons. • Ethene, the simplest unsaturated hydrocarbon, has two carbon atoms joined by a double bond.

13. Simple Organic Compounds 1 Unsaturated Hydrocarbons • Unsaturated compounds with at least one double bond are named with an –ene ending. • These compounds are called alkenes.

14. Simple Organic Compounds 1 Triple Bonds • Unsaturated hydrocarbons also can have triple bonds, as in the structure of ethyne (EH thine). • Ethyne, is a gas used for welding because it produces high heat as it burns. • These unsaturated compounds are called alkynes.

15. Simple Organic Compounds • Compounds that have the same molecular formula but different arrangements, or structures, are calledisomers (I suh murz). Page 412 1 Hydrocarbon Isomers

16. Simple Organic Compounds 1 Hydrocarbon Isomers • Two isomers, butane and isobutane, have different chemical and physical properties because of their different structures.

17. Simple Organic Compounds 1 Hydrocarbons in Rings • Some molecules contain rings. • The carbon atoms of hexane bond together to form a closed ring containing six carbons.

18. Simple Organic Compounds 1 Hydrocarbons in Rings • The prefix cylco- in their names tells you that the molecules are cyclic or ring shaped. • Many natural substances such as sucrose, glucose, and fructose are ring structures. • Ring structures can contain one or more double bonds.

19. Section Check 1 Question 1 A compound that contains only hydrogen and carbon is known as what? A. amino acid B. hydrocarbon B. isomer C. organic compound NC: 4.02

20. Section Check 1 Answer The answer is B. The simplest hydrocarbon is methane, a primary component of natural gas. NC: 4.02

21. Section Check 1 Question 2 What is a methyl group? Answer A methyl group is a fragment of a methane molecule. In particular, it’s one that can bond with another methyl group to build up a larger hydrocarbon. NC: 4.02

22. Section Check 1 Question 3 When all the bonds in a hydrocarbon are single bonds, the molecule is called a(n) _______. A. isomer B. organic compound C. saturated hydrocarbon D. unsaturated hydrocarbon NC: 4.02

23. Section Check 1 Answer The answer is C. You can remember this by thinking that the term saturated means “completely full”; no more hydrogen atoms can be added on to the molecule. NC: 4.02

24. Other Organic Compounds 2 Substituted Hydrocarbons • Chemists change hydrocarbons to make compounds called substituted hydrocarbons. • To make a substituted hydrocarbon, one or more hydrogen atoms are replaced by atoms such as halogens or by groups of atoms.

25. Other Organic Compounds 2 Substituted Hydrocarbons • Such changes result in compounds with chemical properties different from the original hydrocarbon. • For example, when one or more chlorine atoms are added to methane in place of hydrogens, new compounds are formed.

26. Other Organic Compounds 2 Alcohols • Groups of atoms also can be added to hydrocarbons to make different compounds. • Thehydroxyl (hi DROK sul) groupis made up of an oxygen atom and a hydrogen atom joined by a covalent bond. -OH

27. Other Organic Compounds 2 Alcohols • An alcohol is formed when a hydroxyl group replaces a hydrogen atom in a hydrocarbon. • This figure shows the formation of the alcohol methanol.

28. Other Organic Compounds 2 Alcohols • Larger alcohol molecules are formed by adding more carbon atoms to the chain. • The table lists three alcohols with their structures and uses.

29. Other Organic Compounds 2 Carboxylic Acids • Acarboxylic (car BOK sul) groupconsists of a carbon atom that has a double bond with one oxygen atom and a single bond with a hydroxyl group.

30. Other Organic Compounds 2 Carboxylic Acids • Its formula is –COOH. • When a carboxyl group is substituted in a hydrocarbon, the substance formed is called a carboxylic acid. • The simplest carboxylic acid is formic acid. It is found in bee venom.

31. Other Organic Compounds 2 Carboxylic Acids • Many carboxylic acids occur in foods. • Citric acid is found in citrus fruits such as oranges and grapefruit. • Lactic acid is present in sour milk. • Acetic acid dissolved in watervinegaroften is used in salad dressings.

32. Other Organic Compounds 2 Amines • Amines are a group of substituted hydrocarbons formed when an amino group replaces a hydrogen atom. • Anamino (uh ME noh) groupis a nitrogen atom joined by a covalent bond to two hydrogen atoms. • It has the formula –NH2.

33. Other Organic Compounds 2 Amino Acids • When both an amino group (-NH2) and a carboxyl acid group (-COOH) replace hydrogens on the same carbon atom in a molecule, a type of compound known as anamino acidis formed. • Amino acids are essential for human life.

34. Other Organic Compounds 2 The Building Blocks of Protein • Amino acids are the building blocks of proteins, which are an important class of biological molecules needed by living cells. • Twenty different amino acids bond in different combinations to form the variety of proteins that are needed in the human body.

35. Other Organic Compounds 2 The Building Blocks of Protein • Glycine is the simplest amino acid. • It is a methane molecule in which one hydrogen atom has been replaced by an amine group and another has been replaced by a carboxyl group.

36. Section Check 2 Question 1 You can take a hydrocarbon and create a compound with differing properties by replacing some of the hydrogen atoms with halogens. The result will be a _______. Answer The result is a substituted hydrocarbon. You could also add on groups of new atoms. NC: 4.02

37. Section Check 2 Question 2 What does this symbol stand for? –OH NC: 4.02

38. Section Check 2 Answer The symbol refers to a hydroxyl group. NC: 4.02

39. Section Check 2 Question 3 What do you call a carbon atom that has a double bond with one oxygen atom and, at the same time, a single bond with a hydroxyl group? A. amino group B. carboxyl group C. hydroxyl group D. polymer NC: 4.02

40. Section Check 2 Answer The answer is B. Its formula is -COOH. NC: 4.02

41. Biological Compounds 3 What’s a polymer? • A polymeris a molecule made up of many small organic molecules linked together with covalent bonds to form a long chain. • The small, organic molecules that link together to form polymers are calledmonomers.

42. Biological Compounds 3 What’s a polymer? • Polymers produced by living organisms are called natural polymers. • Polymers made in a laboratory are called synthetic polymers.

43. Biological Compounds 3 What’s a polymer? • The unsaturated hydrocarbon ethylene, C2H4, is the monomer of a common polymer used often in plastic bags. • The monomers are bonded together in a chemical reaction calledpolymerization(puh lih muh ruh ZAY shun).

44. Biological Compounds 3 What’s a polymer? • The carbon atoms that were joined by the double bond each have an electron to share with another carbon in another molecule of ethylene. • The process goes on until a long molecule is formed.

45. Biological Compounds 3 Proteins are Polymers • Aproteinis a polymer that consists of a chain of individual amino acids linked together. • Your body cannot function properly without them.

46. Biological Compounds 3 Proteins are Polymers • The various functions in your body are performed by different proteins. • Your body makes many of these proteins by assembling 20 amino acids in different ways. • Eight of the amino acids that are needed to make proteins cannot be produced by your body. • These amino acids, which are called essential amino acids, must come from the food you eat.

47. Biological Compounds 3 Proteins are Polymers • The process by which your body converts amino acids to proteins is shown.

48. Biological Compounds 3 Carbohydrates • A carbohydrateis an organic compound that contains only carbon, hydrogen, and oxygen, usually in a ratio of two hydrogen atoms to one oxygen atom. • The different types of carbohydrates are divided into groupssugars, starches, and cellulose.

49. Biological Compounds 3 Carbohydrates • Glucose and fructose are simple six-carbon carbohydrates found in many fresh and packaged foods. • Glucose and fructose are isomers.

50. Biological Compounds 3 Sugars • Simple sugarsare carbohydrates containing five, six, or seven carbon atoms arranged in a ring.