Chemistry, asked by kennykipa5252, 1 year ago

N-pentane has higher boiling point than neopentane. explain

Answers

Answered by ransan17p4w2rn
23
N-pentane has large surface area compared to neopentane that is the reason it high boiling point

Answered by jmaristela4922
6

Answer:

Pentane has a higher boiling point than 2,2-dimethylpropane.

Explanation:

Branched alkanes normally exhibit lower boiling points than unbranched alkanes of the same carbon content. This occurs because of the greater van der Waals forces that exist between molecules of the unbranched alkanes. The reason why the degree of branching is so important is because intermolecular forces are relatively weak and act over short distances. Branching does not allow molecules to pack tightly together where the forces can exert their maximum attraction hence it takes less energy to pull apart branched molecules than it does to pull apart linear molecules which pack tightly together.  

 The shape of n-pentane, a straight chain, fits well together with other n-pentane molecules, forming tight, well-compacted layers, which are harder to separate. In neopentane, which is 2,2-dimethylpropane, trying to fit neopentane molecules together is difficult because of the substituents. Because of this uneven "packing" it becomes easier to separate and boiling point is lower.

 The stronger the intermolecular forces of attraction, the more energy is required to break those forces which translates into ionic and polar covalent compounds having higher boiling and melting points, higher enthalpy of fusion, and higher enthalpy of vaporization than covalent compounds. The unbranched alkane, in this case pentane, has greater van der Waals forces of attraction because of its greater surface area, thus having a higher boiling point than 2,2-dimethylpropane.

 

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