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How is Aluminium Bromide covalent?

Why does aluminium bromide have covalent bonding and why does it have a low melting point? I thought it was an ionic structure but apparently it is polar covalent. It also doesn't conduct electricity when molten.
Original post by bella0109
Why does aluminium bromide have covalent bonding and why does it have a low melting point? I thought it was an ionic structure but apparently it is polar covalent. It also doesn't conduct electricity when molten.

It’s something to do with the Pauling principle, because Al and Br arent too different in electro negativity making them covalent. You only get ionic compounds with the group 1 and 2 metals really is an easy way to think of it, it has a low melting point because it’s a ‘simple covalent molecule’ with weak van der walls forces between the molecules. It doesn’t conduct electricity because it doesn’t dissociate into ions, we need free moving ions to conduct electricity. Hope this helps
Reply 2
look up the electronegativity values and look here to work out the bond character, that is whether it is ionic, covalent or polar covalent, the tables on the webpage show you how to decide on the type of bonding present

https://www.science-revision.co.uk/A-level_electronegativity_and_bond_character.html

ionic bonding or covalent bonding are extremes most substances have a degree of both! and so properties of both!

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