Carbon Based Life
Alkanes
 70% of cytoplasm is water
 96% of Cell is CHNOPS
 Carbon, hydrogen, nitrogen, oxygen, potassium,
 sulfur
 5,000 different compounds
 Only has to absorb a few nutrients to
 synthesize all of these.
 Can make most everything they need
 Contain carbon
 Have covalent bonds
 Have low melting points
 Have low boiling points
 Burn in air (oxygen)
 Are soluble in nonpolar solvents
 Form large molecules
 Contain only carbon and hydrogen
 • May contain single, double or triple bonds
 between carbon atoms
 •C
C C=C or C C
 • Primary compounds present in petroleum
 Contain C and H only
 Contain single bonds C-C
 Have 4 bonds to every carbon (C) atom
 Are nonpolar
 Show the bonds between each of the atoms
 CH4 , methane
 Condensed Structural Formulas
 Ethane
 CH3 CH3
 Propane
 CH3 CH2 CH3
Name
# carbons
Structural Formula
Methane
1
CH4
Ethane
2
CH3CH3
Propane
3
CH3CH2CH3
Butane
4
CH3CH2CH2CH3
Pentane
5
CH3CH2CH2CH2CH3
Hexane
6
CH3CH2CH2CH2CH2CH3
Heptane
7
CH3CH2CH2CH2CH2CH2CH3
Octane
8
CH3CH2CH2CH2CH2CH2CH2CH3
Nonane
9
CH3 CH2 CH2CH2CH2CH2CH2CH2CH3
Decane
10
CH3CH2CH2CH2CH2CH2CH2CH2CH2CH3
 A. What is the condensed formula for
 B. What is its molecular formula?
 C. What is its name?
 A. CH3CH2CH2CH3
 B. C4H10
 C. butane
 Combustion
 alkane + O2  CO2 + H2O + heat
 Products are always CO2 and H2O
 Complete and balance the reaction for the
complete combustion of C7H16
 Step 1
C7H16 + O2  CO2 + H2O
 Step 2
C7H16 + O2  7 CO2 + 8 H2O
 Step 3
C7H16 + 11 O2  7 CO2 + 8 H2O