Which compound below would be expected to have the highest boiling point?
a) CH3-CH2-CH2-CH2-CH2-CH2-CH3
b) CH3-CH2-CH2-CH2-CH-CH3
|
CH3
c) CH3-CH-CH2-CH-CH3
| |
CH3 CH3
d) CH3
|
CH3-CH-C-CH3
| |
CH3 CH3
I think its A?
See your other post below.
To determine which compound below would be expected to have the highest boiling point, we need to consider the molecular structure and the intermolecular forces present in each compound.
In general, boiling point is affected by the strength of intermolecular forces. The stronger the intermolecular forces, the higher the boiling point.
Let's analyze each compound:
a) CH3-CH2-CH2-CH2-CH2-CH2-CH3: This compound is a straight-chain alkane (heptane) with only London dispersion forces present between its molecules. London dispersion forces are relatively weak intermolecular forces.
b) CH3-CH2-CH2-CH2-CH-CH3:
The presence of a methyl group (-CH3) on the 5th carbon atom creates a branch in the molecule. This compound is a branched alkane (pentane) and also experiences London dispersion forces. However, branching tends to decrease the strength of London dispersion forces, compared to straight-chain alkanes. Therefore, the boiling point of this compound is expected to be lower than in compound a).
c) CH3-CH-CH2-CH-CH3:
This compound is an alkene (hexene) with a double bond between the 2nd and 3rd carbon atoms. Alkenes have stronger intermolecular forces due to the presence of π-bonds, which create dipole-dipole interactions. The boiling point of this compound is expected to be higher than in compounds a) and b).
d) CH3
|
CH3-CH-C-CH3:
This compound is an alkyl halide (2-chloropropane) with a chlorine atom attached to the central carbon. Alkyl halides have stronger intermolecular forces due to the presence of polar bonds and dipole-dipole interactions. The presence of the chlorine atom increases the boiling point of this compound compared to the other compounds mentioned above.
Based on the analysis above, the compound with the highest boiling point would be d) CH3-CH-C-CH3.
Remember that this analysis is based on general trends, and more complex factors can also influence boiling points.