Chapter 25 Section 1

Organic Chemistry-study of compounds containing carbonhydrocarbons- organic compounds that only

contain C and H*remember each carbon forms four bonds simple formula- shows the # and types of atomsstructural formula- shows the #, type and

arrangement of atomsmolecular formula- shows the shapes of molecules

ex- C4H10

-can also write condensed structural formula a different way

CH3(CH2)2CH3

Alkanes (end with –ane, simplest hydrocarbons, contain only single covalent bonds)

# of C Prefix Simple Formula 1 meth- CH4

2 eth- C2H6

3 prop-C3H8

4 but- C4H10

5 pent- C5H12

6 hex- C6H14

7 hept- C7H16

8 oct- C8H18

9 non- C9H20

10 dec- C10H22

-all alkanes that are straight chains are namedn-alkane (means normal)-look back at C4H10 example= n-butane

Branched Chain Alkanes-alkane group takes the place of a hydrogen

atom-called a substituentalkyl group- hydrocarbon substituent

-ends with –yl (take away -ane)-carbon contains one less H-look at # of C to name

ex- CH3 = methyl C2H5 = ethyl

Naming Branched Chain Alkanes1) Find the longest chain = parent molecule

ex- heptane2) # the C’s in the chain, making sure alkyl

groups have lower numbers, can count backwards

ex- 2,3,4 instead of 4,5,63) Add #’s to names of alkyl groups, with a dash

in betweenex- 2-methyl 3-methyl 4-ethyl

4) Use prefixes to denote multiples of the same alkyl groups, commas between #’s

ex- 2,3-dimethyl5) Put alkyl groups in alphabetical order

ignoring prefixesex- 4-ethyl-2,3-dimethyl

6) **Use proper punctuation-commas separate #’s-hyphens separate #’s and letters-no spaces

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-

Drawing Structural Formula From Name1) Find parent chain and draw2) # C’s on parent chain3) Identify substituents and attach to proper C4) Add hydrogen as neededTry These!!5) 3-ethylhexane2) 2,2,4-trimethylpentane3) 3-ethyl-3,4-dimethyloctane