1. Chapter 25 Section 1 Organic Chemistry -study of compounds containing carbon hydrocarbons- organic compounds that only contain C and H *remember each carbon forms four bonds simple formula- shows the # and types of atoms structural formula- shows the #, type and arrangement of atoms molecular formula- shows the shapes of molecules

2. ex- C 4 H 10 -can also write condensed structural formula a different way CH 3 (CH 2 ) 2 CH 3

3. Alkanes (end with –ane, simplest hydrocarbons, contain only single covalent bonds) # of CPrefixSimple Formula 1meth-CH 4 2eth-C 2 H 6 3prop-C 3 H 8 4but-C 4 H 10 5pent-C 5 H 12 6hex-C 6 H 14 7hept-C 7 H 16 8oct-C 8 H 18 9non-C 9 H 20 10dec-C 10 H 22

4. -all alkanes that are straight chains are named n-alkane (means normal) -look back at C 4 H 10 example= n-butane

5. Branched Chain Alkanes -alkane group takes the place of a hydrogen atom -called a substituent alkyl group- hydrocarbon substituent -ends with –yl (take away -ane) -carbon contains one less H -look at # of C to name ex- CH 3 = methyl C 2 H 5 = ethyl

6. Naming Branched Chain Alkanes 1)Find the longest chain = parent molecule ex- heptane 2)# the C’s in the chain, making sure alkyl groups have lower numbers, can count backwards ex- 2,3,4 instead of 4,5,6 3)Add #’s to names of alkyl groups, with a dash in between ex- 2-methyl3-methyl4-ethyl

7. 4)Use prefixes to denote multiples of the same alkyl groups, commas between #’s ex- 2,3-dimethyl 5)Put alkyl groups in alphabetical order ignoring prefixes ex- 4-ethyl-2,3-dimethyl 6)**Use proper punctuation -commas separate #’s -hyphens separate #’s and letters -no spaces

8. 7)Add parent chain name ex- 4-ethyl-2,3-dimethylheptane *Remember prefixes* 2 = di-3 = tri-4 = tetra- 5 = penta-6 = hexa-7 = hepta- 8 = octa-9 = nona-10 = deca-

9. Drawing Structural Formula From Name 1)Find parent chain and draw 2)# C’s on parent chain 3)Identify substituents and attach to proper C 4)Add hydrogen as needed Try These!! 1)3-ethylhexane 2)2,2,4-trimethylpentane 3) 3-ethyl-3,4-dimethyloctane