<span>Since these molecules are all non-polar, the only intermolecular force of attraction will be London dispersion forces. Since these increase by the size of the molecule, the boiling points will decrease in the same order:
Parafin > Heptadecane > hexane > 2,2-dimethylbutane > propane
For these two, hexane > 2,2-dimethylbutane, dispersion forces are greater in a molecule which is longer and unbranched compared to one which is branched and more compact.</span>
Carbon is 12 grams per mole
x=3
Use the pythagorean theorem:
a^2 + b^2 = c^2
4^2 + x^2 = 5^2
16 + x^2 = 25
x^2 = 25-16
x^2 = 9
√x^2 = √9
x = 3