what is the general trend in the boiling point as you compare alkanes of encreasing length?

Answer 1

Generally, as the (linear) alkane increase in length, the boiling point will also increase. This is due to the fact that, although alkane is nonpolar and only has London Force, as the alkane gets longer in a straight chain, the London Forces increases and causes an "Induced" Dipole force so great that it almost "acts" like a polar molecule, hence having high boiling point.

One thing to consider though is that the B.P. not only depend on the length of the alkane but also its shape. If the alkane has branches giving it a tight symmetrical shape, the effects of Induced Dipole will greatly decrease, and it will have relatively low B.P.

I hope this helps. =)

Answer 2

As the length of alkanes increases there is a steady increse in boilin points. This is becasue boiling points depend on weak inter molecular forces called van der waal forces. Vand der waals frces in dependent on surface area, teh longer teh moclecule , teh greater it's surface area, henace the greater it's van der waaals hence a higher boiling point.

Answer 3

Here is chart that compares the boiling of some common alkanes. As you can see from the chart, boiling point goes up as number of carbon in alkane is increased.
http://www.ausetute.com.au/usehydrc.html

Answer 4

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