1.7 CHAPTER 1. ORGANICMOLECULES
Exercise 1 - 3
- Give the structural formula for each of the following:
(a) Octane
(b) CH 3 CH 2 CH 3
(c) CH 3 CH(CH 3 )CH 3
(d) 3-ethyl-pentane- Give the IUPAC name for each of the following organic compounds.
(a)H C
H
H
C
CH 3
H
C
CH 3
CH 3
H
(b) CH 3 CH 2 CH(CH 3 )CH 2 CH 3
(c) CH 3 CH(CH 3 )CH 2 CH(CH 3 )CH 3More practice video solutions or help at http://www.everythingscience.co.za(1.) 01nj (2.) 01nkProperties of the alkanes ESCM
We have already mentioned that the alkanes arerelatively unreactive because of their
stable C-C and C-H bonds. The boiling pointand melting point of these molecules
is determined by their molecular structure, andtheir surface area. Themore carbon
atoms there are in an alkane, the greater the surface area and thereforethe higher the
boiling point. The melting point also increasesas the number of carbon atoms in the
molecule increases. This can be seen in the data in table 1.3.
You will also notice that, when the molecularmass of the alkanes islow (i.e. there
are few carbon atoms),the organic compoundsare gases because the intermolecular
forces are weak. As thenumber of carbon atomsand the molecular massincreases, the
compounds are more likely to be liquids or solids because the intermolecular forces
are stronger.