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Why does tetrachloromethane have a higher boiling point than trichloromethane?
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Marinel Subu
Why does tetrachloromethane have a higher boiling point than trichloromethane?
tetrachloromethane has a higher mollecular mass than that of trichloromethane i.e tetrachloromethane has a Rmm=154 and trichloromethane has a Rmm=118.5
thus the heavier the mollecule the greater the forces of attraction between the mollecules hence a high boiling point and vice versa
tetrachloromethane has a higher mollecular mass than that of trichloromethane i.e tetrachloromethane has a Rmm=154 and trichloromethane has a Rmm=118.5thus the heavier the mollecule the greater the forces of attraction between the mollecules hence a high boiling point and vice versa
Thats a little incomplete. Chloroform has a stronger dipole and that does matter. But it also has weaker london forces than carbon tetrachloride and those outweigh the strength of the dipole forces (it isnt that the dipole forces dont exist).More
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You also need to account for the difference in dispersion forces between the two molecules. Chlorine is much larger than hydrogen. Therefore tetrachloromethane has a larger molecular surface area which increases the intermolecular interaction strength. In this particular case, it outweighs the weak dipole interactions present in trichloromethane.
You also need to account for the difference in dispersion forces between the two molecules. Chlorine is much larger than hydrogen. Therefore tetrachloromethane has a larger molecular surface area which increases the intermolecular interaction strength. In this particular case, it outweighs the weak dipole interactions present in trichloromethane.
tetrachloromethane has a higher mollecular mass than that of trichloromethane i.e tetrachloromethane has a Rmm=154 and trichloromethane has a Rmm=118.5 thus the heavier the mollecule the greater the forces of attraction between the mollecules hence a high boiling point and vice versa
tetrachloromethane has a higher mollecular mass than that of trichloromethane i.e tetrachloromethane has a Rmm=154 and trichloromethane has a Rmm=118.5thus the heavier the mollecule the greater the forces of attraction between the mollecules hence a high boiling point and vice versa
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Chloroform numerically has a relatively strong dipole moment, but the negative charge is distributed over three large chlorine atoms.
The positively charged hydrogen atom finds nothing it could really be attracted to.
Chloroform numerically has a relatively strong dipole moment, but the negative charge is distributed over three large chlorine atoms.
The positively charged hydrogen atom finds nothing it could really be attracted to.
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You also need to account for the difference in dispersion forces between the two molecules. Chlorine is much larger than hydrogen. Therefore tetrachloromethane has a larger molecular surface area which increases the intermolecular interaction strength. In this particular case, it outweighs the weak dipole interactions present in trichloromethane.
You also need to account for the difference in dispersion forces between the two molecules. Chlorine is much larger than hydrogen. Therefore tetrachloromethane has a larger molecular surface area which increases the intermolecular interaction strength. In this particular case, it outweighs the weak dipole interactions present in trichloromethane.
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