Comparison of boiling points

I was comparing boiling points of $\ce{CHCl\_3}$ and $\ce{CH\_3Cl}$. According to me B.P. of $\ce{CHCl\_3}$ should be higher due to it's higher molecular mass than $\ce{CH\_3Cl}$, but the answer is opposite ,ie. B.P. of $\ce{CH\_3Cl}$ $\gt$ B.P. of $\ce{CHCl\_3}$.Why?




Molecular mass has NO pertinence to BP, water and ammonia. Look up the BP of perfluorocyclohexane, hexafluorobenzene, and the hydrocarbons. If I want to volatize iron, ferrocene. If I want to volatize iron more, $\ce{Fe(hfac)\_3}$ where the ligand is the bidentate enolate anion of 1,1,1,5,5,5-hexafluoro-2,4-pentanedione. Big MW. What are the MW and BP of $\ce{UF\_6}$? $\ce{-Si(CH3)\_3}$ also confers volatility.


Boiling points are more about polarizability, intermolecular van der Waals and such. Bigger molecules are overall electronically floppy. Benzene, toluene, xylenes – nice BP steps, but not because of MW. Look up $\ce{SF\_6}$ bp. $\ce{I(CF3)\_7}$ boils near 0 °C. Calculate that MW, and its vapor’s mass/liter at STP compared to dry air at 29 g/liter. 


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> 
> but the answer is opposite ,ie. B.P. of $\ce{CH3Cl}$ > B.P. of $\ce{CHCl3}$.
> 
> 
> 


Really? 


$\ce{CH3Cl}$ has a boiling point of **−24** °C. It is a **gas**. 


$\ce{CHCl3}$ has a boiling point around 61 °C.




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Edit: **Your argumentation is valid, there was probably just some confusion in the notes.**


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