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chemistry gcse

why does boiling point decrease down group 1 of the periodic table? I thought because they'd get bigger in size, there would be more intermolecular force between atoms? so wouldnt it have higher boiling point??
strength of metallic bonding decreases since metal ions get large but still have the same charge, + 1 in the case of alkali metals.. Intermolecular bonding is weak when compared to metallic bonding.

https://science-revision.co.uk/metallic%20bonding.html
Original post by BrightBlueStar11
why does boiling point decrease down group 1 of the periodic table? I thought because they'd get bigger in size, there would be more intermolecular force between atoms? so wouldnt it have higher boiling point??


In the metallic bondings of metal atoms, the positive charged metal ions are fixed to the negative charged electrons what is responsible for this kind of bonds and makes it so strong. That is why their boiling points are pretty high. With the groups in the periodic table down the size of the metals changes, but the charge doesn't, so the boiling point decreases between the metal groups. Compared to this metallic bonding, another ones for non metallic atoms (intermolecular bondings, hydrogen bridge bond and van der waals forces) are pretty weak and easier to break at lower temperatures.
(edited 1 year ago)

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