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Why NeopentaneC(CH3)4 Have Low boiling point then Pentane C5H12? Because the surface area ?

Thanks

[DrBob1]

Just like the butanes, neopentane has a lower boiling point than it's straight chain isomer n-pentane. And for the same reason. Of course the boiing point of the third isomer, isopentane, is right in the middle. But have you noted their BOILING POINTS? Completely reversed!!

[DrBob1]

I mean their melting points

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Yes Pentane Melting point – 129.8 °C, Neopentane Melting point −16.6 °C , Butane Melting point −138.4 °C

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Not both Neopentane and Pentane have a straight chain ?

[Unknown008]

Pentane has a longer straight chain and Neopentane has a shorter one, which is also branched, hence why there is a lower surface area of contact between the latter molecules.

yes Pentane Melting point – 129.8 °C, Neopentane Melting point −16.6 °C , Butane Melting point −138.4 °C

Are you sure those are correct? I thought that pentane is a liquid at room temperature... I guess you mean boiling points.

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Oh OK thanks .

[DrBob1]

n-Pentane has a MELTING POINT of -129.5 oC, this would seem usual for a typical hydrocarbon, Neopentane melts at -16.6 oC; very high for a hydrocarbon of such a low molecular weight. It thus has a liquid range of about 25 Co.

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Thanks for your answer