n-Pentane and isopentane are two isomers of pentane, a hydrocarbon with five carbon atoms and 12 hydrogen atoms. They have the same molecular formula, C5H12, but different structures. n-Pentane has a straight chain of five carbon atoms, while isopentane has a branched chain with four carbon atoms in a row and one carbon atom attached to the second carbon atom. The difference in structure affects their physical properties, such as boiling point. The boiling point of a substance is the temperature at which it changes from liquid to gas. In this report, we will compare the boiling points of n-pentane and isopentane and explain the factors that determine them.
Results and Discussion
The data shows that the boiling point of n-pentane is higher than that of isopentane. According to the web search results, the boiling point of n-pentane is 36.1°C, while the boiling point of isopentane is 27.9°C. This means that n-pentane requires more energy to vaporize than isopentane. The reason for this difference is the intermolecular forces between the molecules. Intermolecular forces are the attractions between molecules that hold them together in a liquid or a solid. The stronger the intermolecular forces, the higher the boiling point.
The main type of intermolecular force in n-pentane and isopentane is the van der Waals force, which is a weak attraction between the temporary dipoles of the molecules. A dipole is a separation of positive and negative charges in a molecule. A temporary dipole is a dipole that forms when the electrons in a molecule are unevenly distributed at a certain moment. The temporary dipole of one molecule can induce a temporary dipole in another molecule, creating a van der Waals force between them.
The strength of the van der Waals force depends on the size and shape of the molecules. The larger and more elongated the molecule, the stronger the van der Waals force. This is because a larger and more elongated molecule has more surface area for the temporary dipoles to interact. n-Pentane has a larger and more elongated molecule than isopentane, as shown in the figure below.
![n-pentane and isopentane structures]
Therefore, n-pentane has stronger van der Waals forces than isopentane, and thus a higher boiling point.
Conclusion and Recommendations
In conclusion, we have analyzed the boiling points of n-pentane and isopentane and found that n-pentane has a higher boiling point than isopentane due to the stronger van der Waals forces between its molecules. This analysis demonstrates the importance of molecular structure in determining the physical properties of substances. We recommend that you use this knowledge to understand the behavior of other hydrocarbons and their isomers.